Whistleblower Response to Agency Investigation Report
OSC File No. DI-21-000239
7 October, 2022

Summary
The report that NASA submitted in response to my whistleblowing complaint entirely fails to
address the concerns I raised about the role of the Mars2020 mission in a Mars Sample Returncampaign, and in fact only further confirms the substance of my filing.
I filed this disclosure because NASA and the Mars Program at the Jet Propulsion Lab were failingto take appropriate precautions to assure that the Earth will be safe from biological risks
associated with bringing samples collected by the M2020 mission to Earth from Mars. The
substance of my complaint is that NASA repeatedly refused to take the steps necessary to ensure
a future Returned Sample Analysis program would have the ability to differentiate rare Mars
organisms from ubiquitous Earth contamination introduced into Mars samples collected for
return by the M2020 mission.
US protocols for the containment and analysis of potentially-biohazardous planetary materials
were first specified in preparation for the Apollo program in the mid-1960s. 'Restricted Earth
Return' guidelines based on these procedures were developed by the international scientificcommunity including the US Space Studies Board, and are maintained by the Committee on Space
Research (COSPAR) of the International Council for Science. In 2017, the UN General Assemblyrecognized COSPAR guidelines as an appropriate approach for demonstrating compliance with
Article IX of the 1967 Outer Space Treaty. In 2020, the US National Academies' Space Studies
Board noted that no other approaches for demonstrating compliance had been identified.
The NASA report supposedly investigating my disclosures focuses entirely on the outboundphase of the M2020 mission, and ignores any link with the Mars Sample Return (MSR) campaign.
However, the M2020 mission has already started MSR, because the sample collection hardware
carried on the M2020 rover is intended for eventual return to Earth.
This is exactly the same behavior that prompted my whistleblowing in the first place.

1/10Regulatory Framework
Presidential Directive/National Security Council-25
In the 1960s, the Apollo Program was required to comply with National Security Action
Memorandum 235 on "Large-Scale Scientific or Technological Experiments with Possible
Adverse Environmental Effects", under which a 1967 Interagency Agreement chartered theInteragency Committee on Back Contamination as the mechanism for assuring protection of the
Earth's biosphere from extraterrestrial sources of contamination (see attached book chapter). In
1977, this memo was superseded by PD/NSC-25, "Large-Scale Scientific or TechnologicalExperiments with Possible Adverse Environmental Effects and Launch of Nuclear Systems into
Space", which is still in effect.
PD/NSC-25 requires consultation between multiple Federal agencies prior to the initiation ofexperiments with potential large-scale adverse environmental effects; however, NASA launched
and landed the M2020 mission on Mars, and is currently collecting samples intended for Earthreturn, without engaging in the consultation required by PD/NSC-25, and without establishingprocedures for Earth Safety Assurance that could mitigate risks from potential Mars biohazards.
In 2020, the Science and Technology Policy Institute (STPI) released a report commissioned by
OSTP on planetary protection policy in the US, that addresses the applicability of PD/NSC-25:
https://www.ida.org/research-and-publications/publications/all/t/to/towards-thedevelopment-of-a-national-planetary-protection-policy
This STPI report also notes how the COVID pandemic is relevant to Mars Sample Return:"All but a small part of this report was completed before the global outbreak of COVID-19, theeffects of which have disrupted the world and damaged its economy. This terrestrial
outbreak underlines the potential danger posed by extraterrestrial life, its consequences notpredictable but now too easily imaginable. "National Environmental Protection Act
The Code of Federal Regulations on NEPA, title 14 section 1216.306, mandates preparation of an
Environmental Impact Statement for projects "which would likely receive a Restricted Earth
Return categorization (as defined in Appendix A to this subpart) from the NASA PlanetaryProtection Office or the NASA Planetary Protection Subcommittee":https://www.ecfr.gov/current/title-14/chapter-V/part-1216/subpart-1216.3/section1216.306
Links to the EISs for M2020 and the 'Mars Sample Return Campaign' are available here:
https://www.nasa.gov/feature/nepa-mars-sample-return-campaign/
In letters dated 7 May and 21 Dec. 2015, following recommendations from the NASA PlanetaryProtection Subcommittee, as Planetary Protection Officer (PPO) I categorized the M2020 project
as 'Restricted Earth Return' at subsystem level, due to the presence of sample storage hardware
intended for return to Earth, per the attached documents CatLtrPartialM2020 and
CatLtrFullM2020.
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Despite the presence of hardware intended for eventual return to Earth, the M2020
Environmental Impact Statement does not mention Mars Sample Return, and omits Earth Safety
Assurance completely: no relevant terms appear in the document.
In April 2021, NASA solicited comments on a Mars Sample Return Environmental Impact
Statement (MSR EIS) that claims to address planetary protection using the "Key strategy: Containor sterilize all material delivered from planets that may harbor life until the material isdemonstrated to be safe."
Who decides when 'the material is demonstrated to be safe' at an adequate level of risk
reduction? What is an adequate level of risk reduction?
Failures to document and control pre-launch Earth contamination that could be introduced into
the samples during collection -- some of which are described in the NASA response to my filing -mean that it will not be possible to assure sensitive detection of rare Mars organisms due topoorly-understood levels of background Earth contamination.
Further incidents of potential contamination during M2020 operations on Mars are documented
in blogs about mission operations, including a report of 'Foreign Object Debris' being found in
the sample collection system:
https://mars.nasa.gov/mars2020/mission/status/396/nasas-perseverance-cores-12thsample-team-assessing-rovers-coring-bit/
https://mars.nasa.gov/mars2020/mission/status/397/perseverance-soon-heads-toenchanted-lake/
In the absence of procedures and oversight having been established, in association with theM2020 mission, for tracking incidents that could affect Earth Safety Assurance and a Marsbiohazard detection protocol -- how will these potential contamination events be fed forward
into post-return Mars biohazard and Earth Safety analyses?
The vast majority of public comments submitted in response to the MSR EIS strongly protest
against bringing Mars samples to Earth until after concerns about potential biohazards are
addressed, in much greater detail than NASA has done to date:https://www.regulations.gov/search/comment?agencyIds=NASA&filter=mars

NASA policy and requirements
Following the then-applicable NASA Policy Document (NPD) 8020.7G, the M2020 categorization
letters provide detailed requirements taken from the then-applicable NASA Procedural
Requirements document NPR 8020.12D, including the statement:"Requirements for Restricted Earth Return missions, of particular relevance to M2020 thoseregarding documentation and oversight, are described in NPR 8020.12D."
The NASA response to my whistleblowing complaint omits any mention of these relevant
requirements, which include:

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5.3.3.6: Reviews and approval of the continuation of the flight mission shall be required atthree stages: 1) prior to launch from Earth; 2) prior to leaving Mars for return to Earth; and3) prior to commitment to Earth reentry.
and5.3.3.11 An independent science and technical advisory committee shall be constituted withoversight responsibilities for materials returned by a Mars sample return mission.
Because the M2020 mission is carrying hardware intended for return to Earth, M2020 is the firstleg of a Mars Sample Return campaign, so an oversight committee should have been convened
prior to the launch of M2020, to ensure appropriate responses to prelaunch contamination
events as well as potential contamination events during Mars operations.
Following precedent and PD/NSC-25, this committee should have included representatives frommultiple Federal agencies, and also international partners, with a structure analogous to theApollo-era Back Contamination Committee.
Instead, NASA convened the so-called Planetary Protection Independent Review Board (PPIRB),
every member of which had a career in space exploration and/or received NASA funding forother professional research. As described in the 2020 SSB report cited below, this committee's
2019 report concluded that containment requirements for Mars samples brought to Earth could
be relaxed, using arguments the SSB found implausible and I, prior to my 2017 removal as PPO,
regularly encountered and had to debunk.

COSPAR and international planetary protection guidelines
NASA requirements are designed to be consistent with both PD/NSC-25 and also international
planetary protection policy, which is maintained by the Committee on Space Research(COSPAR), on the basis of scientific advice from member organizations such as the US National
Academies' Space Studies Board and the European Science Foundation's European Committee on
Space Science.
COSPAR has been responsible for establishing international planetary protection policies fromits' inception in the early 1960s: the COSPAR Planetary Protection Policy was codified in the
1990s to provide comprehensive guidelines for complying with planetary contamination
provisions of the Outer Space Treaty. In 2017, The United Nations General Assembly explicitly
recognized the COSPAR guidelines as demonstrating compliance with the Outer Space Treaty, by
accepting the report of the Committee on the Peaceful Uses of Outer Space, which includes thestatement:"The Committee also noted the long-standing role of COSPAR in maintaining the planetary
protection policy as a reference standard for spacefaring nations and in guiding compliancewith article IX of the Outer Space Treaty."
The full report is available at:https://documents-dds-ny.un.org/doc/UNDOC/GEN/V17/044/69/PDF/V1704469.pdf

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Outer Space Treaty
Article VI of the US Constitution recognizes treaties ratified by the United States as 'the supreme
Law of the Land'.
Although exactly what this means in regard to space exploration is open to dispute, as reviewed
in the STPI/OSTP report cited above and also the Space Studies Board (SSB) report cited below,
sections of the 1967 Treaty on Principles Governing the Activities of States in the Exploration and
Use of Outer Space, including the Moon and Other Celestial Bodies that are relevant to planetary
protection, and particularly Mars Sample Return as performed by a consortium of governmental
agencies like NASA and non-governmental entities such as the Jet Propulsion Lab (JPL), include:
Article VI“States Parties to the Treaty shall bear international responsibility for national activities inouter space, including the Moon and other celestial bodies, whether such activities arecarried on by governmental agencies or by non-governmental entities...”
Article VII“Each State Party to the Treaty that launches or procures the launching of an object into outerspace, including the Moon and other celestial bodies, and each State Party from whose
territory or facility an object is launched, is internationally liable for damage...”Article IX“...States Parties to the Treaty shall pursue studies of outer space including the Moon andother celestial bodies, and conduct exploration of them so as to avoid their harmful
contamination and also adverse changes in the environment of the Earth resulting from theintroduction of extraterrestrial matter and, where necessary, shall adopt appropriate
measures for this purpose...”

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Scientific Motivations for Planetary Protection
Planetary protection guidelines for Restricted Earth Return missions have been developed using
the best available scientific justification, that supports the policy and regulatory framework thathas provided for Earth Safety Assurance since the Apollo program.
Results from the Mars Science Laboratory mission provide a clear illustration of why stringent
contamination control is critical for experiments intended to detect extraterrestrial
biosignatures.
In 2015, mission scientists Freissinet et al. reported high-confidence detections of carbon-based
compounds from Mars, using the Sample Analysis at Mars (SAM) instrument on the Curiosity
rover. This detection of Mars carbon-based compounds was quite challenging, due to high levelsof Earth contamination that were introduced into the Mars material during sample collection:
the conclusion that a subset of compounds was definitively from Mars required thedemonstration they were not contaminants from Earth:https://doi.org/10.1016/j.pss.2016.06.007
In 2018, Guzman et al. compared archival data from the Viking missions in the 1970s with thedata from SAM, and reported the presence of these same carbon-based compounds:
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2018JE005544
After performing an extensive evaluation of possible Earth contamination sources for the organic
compounds detected by Viking, these investigators conclude:"the Viking GCMS experiment could have detected organic carbon indigenous to a martian
sample for the first time, almost 40 years before the detection by the Curiosity rover's SAM
experiment."
Viking mission scientists interpreted the carbon compounds detected by the GCMS instrument as
being due exclusively to Earth contamination. This 'failure' to detect carbon-based compounds
from Mars was interpreted as indicating an absence of Mars life: as a result, Mars exploration
was put on hold for over 20 years.
In contrast, Gilbert Levin, the principal investigator of the independent 'Labeled Release' life
detection instrument on Viking, continued to publish papers arguing that this experiment had
produced evidence of biological metabolism by Mars organisms, until his death in 2021:
https://en.wikipedia.org/wiki/Gilbert_LevinOf the two life detection experiments on Viking, investigators supporting one experiment
incorrectly interpreted their results as due entirely to Earth contamination, while the other met
pre-specified criteria for detecting 'life', although with alternative explanations for the results.
An incorrect interpretation of the GCMS experiment was believed, over possibly-correct but
ambiguous Labeled Release results. What would have been the history of Mars exploration, if thedetection of carbon-based compounds on Mars had been recognized correctly in 1976?
What could be the consequences of Mars Sample Return, if overprinting from Earthcontamination again prevents detection of faint signals indicating the presence of Mars life?
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iMARS and the scientific community
In preparation for a Mars Sample Return campaign planned to start in the 2010s, theInternational Mars Exploration Working Group convened the study group for an 'international
Mars Architecture for Return of Samples (iMARS) that produced a series of reports, described at:https://planetary.aeronomie.be/index.php/projects/old-projects/imars
These reports covered in detail how samples should be handled for Mars biohazard assessment,
including what kinds of controls should be performed to mitigate interference from Earthcontamination.
Although not implemented in practice on M2020, the iMARS reports involved substantial
participation from the JPL Mars Program, to the extent that the individual reports are hosted on
the Mars Exploration Program Analysis Group website at JPL:
http://mepag.jpl.nasa.gov/reports/iMARS_FinalReport.pdf
http://mepag.jpl.nasa.gov/reports/imarsPII_report_2016.pdf
JPL has a long history of resisting planetary protection precautions, as reviewed in the attachedbook chapter and STPI/OSTP report. The Viking GCMS was the only experiment provided by JPL,
and was also the only instrument on either lander to fail: a fact still taught to incoming JPL staff,
blamed on planetary protection. Entrenched negative cultural attitudes seem likely to becontributing factors in the Mars Program's avoidance of steps necessary to mitigate thedemonstrated potential for Earth contamination to overprint signals from Mars.

US National Academies' Space Studies Board
In addition to the international planetary protection guidelines maintained by the International
Council for Science, of which the US National Academies is a member, NASA policies are also
based on detailed recommendations from the SSB, in reports going back to the WestEx report of1959, that had Carl Sagan as a co-author.
SSB publications are available from the Academies' website. The most recent publication onplanetary protection policy is from 2020, and is an assessment of how consistent the changes
proposed by NASA's 2019 PPIRB are with historical planetary protection policy and practice:https://nap.nationalacademies.org/catalog/25773/assessment-of-the-report-of-nasasplanetary-protection-independent-review-board
The SSB identifies a number of problematic proposals that emphasize the need for NASA toensure external coordination on policy issues, although they don't explicitly question the PPIRB
membership composition in the context of 'independence'. Notably, in regard to "Areas ofInconsistency and Concern," this SSB report includes the following statement:"The committee finds that the naturally occurring transport of martian materials to Earth is
not a scientifically compelling reason to alter planetary protection policies for returned
samples from Mars."

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Narrative Response to NASA's 'investigation' report
Overall, NASA's investigation evaded the entire point of my disclosure, which was about Earth
Safety Assurance, specifically the fact that NASA will be unable to differentiate Earthcontamination from potential Mars life in samples collected by M2020 and brought to Earth, andtherefore will have no way of understanding how biohazardous these Mars samples could be.
This evasion is first indicated by the statement on pg. 1, that pretends to summarize some of myallegations:"NASA officials oversaw the erosion of the agency’s planetary protection requirements,
resulting in lowered cleanliness standards for Mars 2020 and risking the integrity of future
missions;"
My disclosure is not about 'the integrity of future missions' -- it's about NASA and JPL
management engaging in a long history of deliberate action that renders the agency unable toassure the safety of Earth when returning samples from Mars. The M2020 mission failed both toensure sufficiently low levels of Earth contamination on hardware for return, and to maintaindetailed records of Earth contamination possibly introduced into Mars samples.
High levels of Earth contamination increase instrument background, which reduces detection
sensitivity for Mars organisms because small signals just get buried in the noise.
For example: what compounds could be introduced into the M2020 samples by the Foreign
Object Debris that mission bloggers described as being discovered in the collection hardware
during collection of sample 12? NASA's report neglected to mention similar potential
contamination events, although this one and others took place before submission.
That NASA is completely ignoring serious concerns about potential Mars biohazards and Earth
Safety Assurance in relation to M2020 is further demonstrated, in NASA's report, by thesummary of requirements applied to the M2020 mission (pg. 7) -- a number of the most relevant
Category V Restricted Earth Return requirements are omitted from the list provided.
NPR 8020.12D requirement 5.3.3.1 "Samples returned from Mars by spacecraft shall becontained and treated as though potentially hazardous until demonstrated otherwise." is notably
missing, as are requirements 5.3.3.6-11 describing required steps for assuring safety of the Earthfrom returned Mars samples.
COSPAR guidelines and NASA requirements for Mars Sample Return that relate to preventing a
potential release of Mars life on Earth were written under the assumption that the entire sample
collection and return process would be carried out by a single mission. Under a multi-mission
scenario, the post-return cleanliness requirements need to feed backwards onto the initialsample collection mission, to avoid exactly what NASA and JPL are doing with M2020.
If the first sample collection mission doesn't both ensure appropriately high levels of cleanlinessand also retain detailed records describing what was done, there will be no way to determine
whether indications of possible biology in the returned samples represent Mars life or Earthcontamination. This basis for Earth Return guidelines has been clearly stated over decades inrecommendations from the Space Studies Board, as well as both reports from the iMARS study
team (see above) -- which NASA co-led with ESA, but has subsequently disregarded.
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During the Apollo Program, the applicable regulation under which the Lunar Back Contamination
Committee was constituted was PD/NSC-25, on "Scientific or Technological Experiments with
Possible Large Scale Adverse Environmental Effects...", and the STPI/OSTP report cited above
concluded that this regulation also should apply to Mars Sample Return. Decades of SSB
recommendations, as well as long-standing NASA requirements documents, support theestablishment of a modern equivalent of the Apollo-era Back Contamination Committee to exert
independent oversight as part of the preparations for Mars Sample Return.
NASA used to have a FACA-chartered NASA Planetary Protection Advisory Committee (charterattached as PPACcharter), that included agency and international liaison members specifically toserve as an informal interim coordination mechanism. These liaisons were eliminated from theTerms of Reference of the non-FACA Planetary Protection Subcommittee in 2009 (attached as
PPStor), before it was disbanded in 2016. Timing suggests these decisions could be a response
to my actions as PPO in highlighting the need -- to NASA upper management, as well as the State
Dept. and the FAA -- to establish a new Back Contamination Committee for Mars Sample Return.
The ad hoc "Boards, Working Groups, Teams, and Reviews" suggested on pg 38 of NASA's report-- particularly if convened by the Mars Program or otherwise supported by NASA/SMD -- areentirely opaque to oversight, and have the potential to be highly conflicted if, as with the PPIRB,
the membership is composed of NASA-funded or industry insiders. The 2020 SSB report cited
above emphasized the particular importance of truly independent and balanced oversight.
Committees that are funded directly by the organization they purport to oversee are much less'independent' that the NASA Advisory Council subcommittee used to be, even after the FACA
charter was lost. Across multiple 'independent' reviews of M2020 implementation, NASA
experts who participated, and expressed views that diverged from the Mars Program party line,
were subsequently penalized.
The most blatant demonstration that NASA has allowed M2020 to evade requirements related to
Earth Safety Assurance is provided by the extremely brief discussion of contamination-related
issues in NASA's report responding to my filing.
The 'System Deviation' mentioned on pg. 15 was apparently granted on the basis of a claim fromthe project that "Mars/Earth safety is unaffected." Further down the page -- after stating that
M2020 samples could be contaminated above baseline levels -- NASA's report notes:"Failure to meet the baseline total organic does not present a significant threat to planetary
protection but potentially affects some Mars sample return science".
In the context of detecting potential indications of Mars life, the 2018 iMARS report came toprecisely the opposite conclusion about contamination affecting science but not planetary
protection. On pg. 16, the iMARS team concludes:"Scientists now recognise that sample analyses required to meet planetary protection
requirements are more or less the same ones they would want to perform in the interest ofscientific investigation"
This means that degradation of science related to Mars biosignature detection also degrades
Earth Safety Assurance. NASA's repetition of claims that increases in Earth contamination do notaffect Earth Safety Assurance demonstrates exactly the substance of my disclosure.
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Pp. 20-22 of NASA's report describe the steps taken by the M2020 project to document the levelof cleanliness the Sampling and Caching system, particularly the 'Fluid Mechanical Biobarriers'
was predicted to achieve. The explicit assumption by M2020 that contamination from areas of
the rover not considered 'sample intimate hardware' would never reach the samples is notquestioned by the author of NASA's report -- which is odd, because this person should be quite
familiar with the Genesis mission, where contamination redistributed from distant parts of thespacecraft has been an enduring scientific challenge:
https://curator.jsc.nasa.gov/genesis/contamination.cfm
One of the major objections to M2020's proposed implementation, raised by the PPO and PPS in
the last meeting before the PPS was disbanded in 2016, is that the assumptions about theperformance of the sampling/caching hardware were not adequately tested. Multiple additional'independent' reviewers also expressed concerns that the 'challenge' protocol and CFD modelingproposed by M2020 did not accurately represent the potential for contamination, includingNASA employees also subsequently blacklisted for these contributions. Neither of the M2020
approachs considered more than a very small number of diurnal pressure/temperature cycles -despite the sample collection hardware being exposed on Mars for many hundreds of days -- nor
were the electrostatic and electromagnetic environments evaluated under deployed conditions.
Even if the contamination control measures might have been adequate for hardware maintainedat the mandated level of cleanliness, the sections of NASA's report on 'Verification andValidation' and 'Issues' describe a large number of cleanliness violations during assembly, test,
and launch. Given the lax attitude to these violations demonstrated by NASA in this report, thepotential for additional introduction of undocumented contamination is high. This further
degrades NASA's ability to assure Earth Safety by ensuring sensitive detection of possible Marsbiohazards in returned samples.
In conclusion: NASA's report documents confirmation that NASA has not taken the necessary
steps to provide an appropriate level of Earth Safety Assurance for samples collected by the
M2020 mission, as mandated in NASA requirements and COSPAR guidelines, following
recommendations from the Space Studies Board and European Space Science Committee, andfully endorsed by multiple international scientific teams including iMARS.
When I was PPO, and attempting to impose Restricted Earth Return requirements on the M2020
mission -- specifically including feed-forward from the M2020 mission into the Earth Returncampaign -- the Mars Program and JPL management refused to comply with requirements they
perceived as being too inconvenient and costly. Fulfilling my responsibilities as PPO specified in
NPD 8020.7, I communicated these violations to the highest levels of NASA management, andfiled a whistleblowing disclosure after being penalized for doing my job.
NASA's investigation report fails to identify any actions taken to ensure the M2020 projectcomplies with planetary protection requirements for Restricted Earth Return. After the sample
collection leg of a proposed Mars Sample Return mission has landed on Mars, it is physically
impossible to determine whether the amount of Earth contamination being introduced into thesamples is likely to swamp out a sensitive detection of Mars life.
Many of the public comments on the NEPA MSR EIS website take a very clear position: to avoid
inadvertent release of possible Mars organisms on Earth, samples that are too contaminated toallow sensitive detection of Mars life should not be brought to Earth.
10/10National Aeronautics andSpace Administration
Headquarters
Washington, DC 20546-0001

21 Dec., 2015

Rep y to Attn of: Science Mission Directorate

Project Manager
M2020 Project
Jet Propulsion Laboratory
4800 Oak Grove Drive
Pasadena, California 91109

Subject: Full Planetary Protection Categorization of the Mars 2020 Mission
Dear:

I have reviewed the requests that the Project has submitted for a Planetary Protection
Categorization of the M2020 mission. Those communications, taken together, do not provide
sufficient information to ascertain the degree to which Mars 2020 Project is proposing to deviate
from requirements specified in NASA Procedural Requirements document (NPR) 8020.12D.
Therefore, this categorization letter reiterates the standard set of requirements for the mission
described, taken from NPR 8020.12D and clarified in the Partial Categorization Letter dated 7 May
2015. If the Project intends to propose deviations from these requirements, they should be justified
using the formal deviation request process developed for this purpose.
The mission description provided in support of the Project's categorization requests indicates that
the M2020 flight system is based on MSL heritage hardware, and will consist of a cruise stage;entry, descent, and landing system; and a radiothermal-powered rover with science payload. The
rover payload includes a novel subsurface sampling system and novel caching hardware that are
intended to collect and enclose samples for possible future return to Earth.
In addition, information describing instruments selected for the M2020 mission indicates that therover-carried science payload has the capability to perform near-surface measurements of organic'biosignature' compounds in situ, with at least parts per million (ppm) sensitivity.
The M2020 Project plans to exclude landing in or on Mars Special Regions.
Due to the presence of a "returnable" sample caching system, including hardware that is intended
in future to be returned to Earth, the M2020 mission represents the first element of a possible futureMars Sample Return campaign, and therefore receives a designation of Planetary Protection
Category V Restricted Earth Return. Requirements for Restricted Earth Return missions, ofparticular relevance to M2020 those regarding documentation and oversight, are described in NPR
8020.12D.
To support this categorization, the outbound leg of the M2020 mission shall be required to comply
with requirements for Planetary Protection Category IVb, which may be implemented at subsystemlevel, as a mission to Mars that will not access Special Regions but that will conduct "scientificinvestigations of possible extraterrestrial life forms, precursors, and remnants" per the NASA policy
statement in NPD 8020.7G. These requirements apply to both hardware caching samples for
return to Earth, and to in situ biosignature detection instruments, which incur requirements tomaintain contamination at levels “driven by the nature and sensitivity" of the instruments, per NPR

NASA Planetary Protection Officer

8020.12D. All requirements contained within NPR 8020.12D that are relevant to a Category IVb
Mars mission shall apply to the M2020 mission.
Some relevant Category IVb-subsystem and Category V Restricted Earth Return requirements fromNPR 8020.12D are clarified below. In some cases, the language below reiterates or refers tolanguage contained in M2020 Project Level 1 requirements; the purpose of this is to ensure
appropriate coordination and oversight by the NASA Planetary Protection Officer (PPO) of projectrequirements relevant to planetary protection and possible future sample return.
Absence from this list in no way implies that other relevant requirements from NPR 8020.12D arewaived. Because the M2020 Project is still developing a design and operational approach forsample caching, and considering information received by my office that the M2020 payload
accommodation has not yet closed, additional planetary protection requirements may be levied toensure compliance of the M2020 final architecture, per NPR 8020.12D Section 2.7.1.
1. Clarification of NPR 8020.12D Section 5.3.2.2.b implemented at subsystem level:
Requirements for in situ instruments investigating 'precursors or remnants' of life:
1.1 The M2020 Project shall prevent contamination by Earth compounds of Mars materials
subjected to in situ analysis above the levels negotiated with instrument providers as part of
instrument accommodations.
a) pre-launch cleanliness levels and post-launch operations necessary to ensure adequate
contamination prevention shall be derived by the Project and reported as part of
implementing planetary protection requirementsb) compliance shall be monitored by the PPO in addition to project/program processes
Requirements for hardware collecting samples intended for possible future return to Earth:
1.2 Hardware subsystems that are involved in the acquisition, delivery, and storage of samples
intended for future return to Earth shall be cleaned to a level of <300 heat resistant 'spores'2
per m of hardware surface and also cleaned to levels of organic cleanliness derived as
described in section 3.1.b of this letter, enclosed in a physical biobarrier that is not
subsequently opened until operations at Mars, and subjected to a validated biologicalreduction process (e.g., Dry Heat Microbial Reduction) that achieves at least four orders ofmagnitude of microbial reduction.
1.3 Recontamination shall be prevented as described under section 3 of this letter.
1.4 Pre-launch hardware cleanliness shall be verified by test:a) verification of biological cleanliness shall be performed following accepted NASA
processesb) a similar level of verification shall be performed for organic cleanliness, following
validated processesc) a microbial inventory covering at least 99% of organisms present, as demonstrated byrarefaction curve analysis using total environmental sequencing of samples collectedfrom subsystem hardware assembly environments, shall be provided in the M2020 PostLaunch Reportd) typical PPO audit activities, as described for biological cleanliness in NPR 8020.12, shallbe accommodated for both biological and organic cleanliness2. Clarification of NPR 8020.12D Sections 5.3.2.3.c and 5.3.2.5.c, requirements for avoiding accessto or creation of spacecraft-induced special regions:
2.1 Due to the presence of a radiothermal generator (RTG) used to power the M2020 rover, theM2020 Project shall ensure that candidate landing sites exclude the following from the postparachute-opening 3-sigma landing ellipse:

2
Mars 2020 Planetary Protection Categorization, December 2015

a) locations with ice or hydrated minerals at depths of <5 meters (based on MSL impact
calculations), for which exposure to an RTG could cause liquid to be liberated sufficient tomobilize a particle of <50nm in sizeb) Special Regions as formally defined in NPR 8020.12D Section 5.3.2.5 or as modified bymutual agreement prior to launch, pending evaluation of the definition rendered by the
2014-15 MEPAG/SSB/ESF evaluations, and subject to review by the NASA PlanetaryProtection Subcommitteec) transient Special Regions on the rover created by the presence of an RTG are included inthese constraints: their absence shall be demonstrated by test and analysis pre-launch.
Any evidence collected during rover operations that suggest higher potential for special
regions than predicted shall be reported per 2.4.
2.2 In addition to the standard reviews, the final candidate landing sites shall undergo an
independent review, organized by the PPO, as part of the pre-launch landing site selection
process and prior to the preparation and presentation of landing site options to the Science
Mission Directorate Associate Administrator.
2.3 Later access to locations identified in 2.1, via either vertical or horizontal mobility of roverelements, shall be prohibited.
2.4 Checkpoints shall be instituted as a standard element of rover operations, to ensure
appropriate reporting to and oversight by the NASA PPO.
3. Clarification of NPR 8020.12D Sections 5.3.3.2 and 5.3.2.7, requirements for Category V
Restricted Earth Return:
3.1 The M2020 Project shall ensure that Mars samples intended for possible future return are notcontaminated by terrestrial organic compounds or viable organisms at levels above thosespecified below, through final deposition of sample tubes on Mars:a) the probability that a single viable organism is introduced into each sample shall be lessthan the limit obtained by multiplying the internal surface area of a sealed sample tube, in
2
2
m , by the Viking post-sterilization surface bioburden limit of 0.03 viable organisms per mb) terrestrial organic contamination shall be limited to levels below < 1 ppb of any Tier 1organic compound per sample, and < 10 ppb Total Organic Carbon per sample. A
deviation may be requested in the event that the methods used to validate thisrequirement can with confidence distinguish between the draft Level 1 baseline (10 ppb)
and threshold (40 ppb) requirements, and measurements demonstrate compliance withthreshold but not baseline. (reference: draft Project L1 requirements and the 2014 MEP
Organic Contamination Panel output)
3.2 Sample tubes shall be designed for opening after return to Earth in a manner that will prevent
contamination of samples above permitted limits during sample extraction.
3.3 The M2020 Project shall ensure that hardware is maintained at cleanliness levels necessary
to comply with organic compound and viable organism contamination requirements.
Specifically, the Project shall:a) derive the levels of hardware cleanliness necessary to ensure compliance, taking into
account the potential for volatile and particulate recontamination at each phase of themissionb) demonstrate, by analysis and test, that recontamination prevention approaches ensure
maintenance of required sample cleanliness during all nominal rover operations throughfinal deposition of sample tubes on Marsc) develop cleanliness verification strategies to document compliance with pre-launchhardware cleanliness derived requirementsd) submit the above to OPP for review, acceptance, and subsequent compliance auditing
3.4 Documentation of relevant information on the M2020 mission, including detailed information
about operations at Mars, and also information on interfaces between the M2020 Project and3Mars 2020 Planetary Protection Categorization, December 2015

National Aeronautics andSpace Administration
Headquarters
Washington, DC 20546-0001

07 May, 2015

Rep y to Attn of: Science Mission Directorate

Project Manager
M2020 Project
Jet Propulsion Lab
4800 Oak Grove Dr.
Pasadena, CA 91109

Subject: Partial Planetary Protection Categorization of the Mars 2020 Mission
Dear:

I have reviewed the multiple requests that the project has submitted for a Planetary Protection
Categorization of the M2020 mission. Currently, insufficient information has been received by myoffice to provide a complete Planetary Protection Categorization; however, this partial
categorization letter is provided in recognition of the impending Key Decision Point B Directorate
Program Management Council review, to demonstrate progress on establishing planetary protection
requirements for the M2020 mission. The project is currently engaged in processes outlined in
NPR 8020.12D, including Appendix C, communicating with the Planetary Protection Officer (PPO).
The mission description information provided in support of the categorization requests to dateindicates that the M2020 flight system is based on MSL heritage and will consist of a cruise stage;entry, descent, and landing system; and a radiothermal-powered rover with science payload. The
rover payload includes a subsurface sampling system and caching hardware that are intended tocollect and enclose samples for possible future return to Earth.
In addition, information describing instruments selected for the M2020 mission indicates that therover-carried science payload has the capability to perform near-surface measurements of organic'biosignature' compounds in situ, with at least ppm sensitivity.
The M2020 project plans to exclude landing in or on Mars Special Regions.
Based on information provided in your letters and other information available to the Office ofPlanetary Protection, the outbound leg of the M2020 mission shall be required to comply withrequirements for Planetary Protection Category IVb implemented at subsystem level, as a mission
to Mars that will not access Special Regions, but that will conduct "scientific investigations ofpossible extraterrestrial life forms, precursors, and remnants" per the NASA policy statement in
NPD 8020.7G, both in situ and if cached samples are returned to Earth. All requirements contained
within NPR 8020.12D that are relevant to a Category IVb Mars mission shall apply to the M2020
mission.
In addition, due to the presence of a "returnable" sample cache including hardware that is intended
in future to be returned to Earth, the M2020 mission represents the first element of a possible futureMars Sample Return campaign, and hereby receives a designation of Planetary Protection
Category V Restricted Earth Return, per NASA and international policy. Requirements for
Restricted Earth Return missions, of particular relevance to M2020 those regarding documentationand oversight, are also described in NPR 8020.12D.

NASA Planetary Protection Officer

Some relevant Category IVb-subsystem and Category V Restricted Earth Return requirements fromNPR 8020.12D are clarified below. In some cases, the language below reiterates or refers tolanguage contained in M2020 Project Level 1 requirements; the purpose of this is to ensure
appropriate coordination and oversight by the PPO of project requirements relevant to planetary
protection and possible future sample return.
Absence from this list in no way implies that other relevant requirements from NPR 8020.12D arewaived. Because the M2020 project is still developing a design and operational approach forsample caching, additional planetary protection requirements may be levied as the M2020
architecture is finalized, per NPR 8020.12D Section 2.7.1.
1. Clarification of NPR 8020.12D Section 5.3.2.2.b implemented at subsystem level, requirements
for in situ instruments investigating 'precursors or remnants' of life:
1.1 The M2020 project shall prevent contamination by Earth compounds of Mars materials
subjected to in situ analysis above the levels negotiated with instrument providers as part of
instrument accommodations.
a) pre-launch cleanliness levels and post-launch operations necessary to ensure adequate
contamination prevention shall be derived by the project and reported as part of
implementing planetary protection requirementsb) compliance shall be monitored by the PPO in addition to project/program processes
2. Clarification of NPR 8020.12D Sections 5.3.2.3.c and 5.3.2.5.c, requirements for avoiding accessto or creation of spacecraft-induced special regions:
2.1 Due to the presence of a radiothermal generator (RTG) used to power the M2020 rover, theM2020 project shall ensure that candidate landing sites exclude the following from the postparachute-opening 3-sigma landing ellipse:a) locations with ice or hydrated minerals at depths of <5 meters (based on MSL impact
calculations), for which exposure to an RTG could cause liquid to be liberated sufficient tomobilize a particle of <50nm in sizeb) Special Regions as formally defined in NPR 8020.12D Section 5.3.2.5 or as modified bymutual agreement prior to launch, pending evaluation of the definition rendered by the
2014-15 MEPAG/SSB/ESF evaluations, and subject to review by the NASA PlanetaryProtection Subcommittee
2.2 In addition to the standard reviews, the final candidate landing sites shall undergo an
independent review, organized by the PPO, as part of the pre-launch landing site selection
process and prior to the preparation and presentation of landing site options to the Science
Mission Directorate Associate Administrator.
2.3 Later access to locations identified in 2.2.1, via either vertical or horizontal mobility of roverelements, shall be prohibited.
3. Clarification of NPR 8020.12D Sections 5.3.3.2 and 5.3.2.7, requirements for Category V
Restricted Earth Return:
3.1 The M2020 project shall ensure that Mars samples intended for possible future return are notcontaminated by terrestrial organic compounds or viable organisms at levels above thosespecified below, through final deposition of sample tubes on Mars:a) the probability that a single viable organism is introduced into each sample shall be lessthan the limit obtained by multiplying the internal surface area of a sealed sample tube, in
2
2
m , by the Viking post-sterilization surface bioburden limit of 0.03 viable organisms per mb) terrestrial organic contamination shall be limited to levels below < 1 ppb of any Tier 1organic compound per sample; < 10 ppb Total Organic Carbon per sample (reference:draft Project L1 requirements and the 2014 MEP Organic Contamination Panel output)

2

Mars 2020 Partial Planetary Protection Categorization, May 2015

3.2 Sample tubes shall be designed for opening after return to Earth in a manner that prevents
additional contamination of samples during extraction.
3.3 The M2020 project shall ensure that hardware is maintained at cleanliness levels necessary
to comply with organic compound and viable organism contamination requirements.
Specifically, the project shall:a) derive the levels of hardware cleanliness necessary to ensure compliance, taking into
account the potential for volatile and particulate recontamination at each phase of themissionb) demonstrate, by analysis and test, that recontamination prevention approaches ensure
maintenance of required sample cleanliness during all nominal rover operations throughfinal deposition of sample tubes on Marsc) develop cleanliness verification strategies to document compliance with pre-launchhardware cleanliness derived requirementsd) submit the above to OPP for review, acceptance, and subsequent compliance auditing
In addition to the above, planetary protection requirements derived from NPR 8020.12D, as well as
additional requirements developed during the ongoing process of categorization per NPR 8020.12D
Appendix C, shall be formally documented in a subsequent update to this Partial Categorization
Letter and the appropriate Project documents, including the Program Level Requirements Appendix(Level 1 requirements) and associated lower level requirements as well as documentation required
by NPR 8020.12D.
To ensure appropriate coordination and oversight by the PPO of project requirements relevant toplanetary protection and possible future sample return, all changes to M2020 Project Level 1
requirements relevant to planetary protection, as well as lower-level derived requirements affecting
planetary protection compliance that would normally come under project or program control, shallbe submitted to the PPO for approval prior to acceptance or implementation by M2020.
I look forward to continuing work with the M2020 project on implementation of planetary protection
requirements on this very exciting opportunity to prepare for returning samples from Mars. Bestwishes for the success of your mission.

3

Mars 2020 Partial Planetary Protection Categorization, May 2015

12.5

Planetary Protection

CONTENTS
12.5.1 Introduction ..................................................................................................................................................................819
12.5.1.1 Overview of Planetary Protection Considerations ......................................................................................819
12.5.1.2 Relationship to Astrobiology and Planetary Exploration........................................................................... 820
12.5.1.3 Interfaces with Wider Society .................................................................................................................... 820
12.5.2 Planetary Protection: Definition and Scope ................................................................................................................ 820
12.5.2.1 Forward Contamination Concerns ............................................................................................................. 821
12.5.2.2 Backward Contamination Concerns .......................................................................................................... 821
12.5.2.3 International, National, and Agency-Level Obligations and Responsibilities ........................................... 821
12.5.3 A Brief History of Planetary Protection ..................................................................................................................... 822
12.5.3.1 Early Concerns ........................................................................................................................................... 822
12.5.3.2 Evolution of Planetary Protection Policy and Guidelines .......................................................................... 823
12.5.3.3 Planetary Protection Policy Applied to Early Programs ........................................................................... 824
12.5.3.3.1 Soviet Decontamination Efforts ............................................................................................. 824
12.5.3.3.2 Ranger..................................................................................................................................... 824
12.5.3.3.3 Apollo ..................................................................................................................................... 825
12.5.3.3.4 Viking ..................................................................................................................................... 826
12.5.4 Application to Missions in Preparation....................................................................................................................... 828
12.5.4.1 Outer Planets Missions............................................................................................................................... 828
12.5.4.1.1 Probability of Contamination ................................................................................................. 828
12.5.4.1.2 Cleanliness and Life Detection .............................................................................................. 828
12.5.4.2 Mars Missions ............................................................................................................................................ 828
12.5.4.2.1 Planetary Protection Requirements for Mars: It’s Complicated ............................................ 828
12.5.4.2.2 “Average” Mars....................................................................................................................... 829
12.5.4.2.3 Special Regions on Mars ........................................................................................................ 829
12.5.4.2.4 Mars Life Detection................................................................................................................ 829
12.5.4.2.5 Mars Sample Return ............................................................................................................... 830
12.5.4.3 Human Missions ........................................................................................................................................ 830
12.5.5 Open Issues in International Policy ............................................................................................................................ 831
12.5.5.1 Relationship of International Policy to National Obligations .................................................................... 831
12.5.5.2 Application of Planetary Protection Guidelines to Commercial Missions ................................................ 831
12.5.5.3 International Concerns Around Restricted Earth Return .......................................................................... 832
12.5.6 Societal Considerations ............................................................................................................................................... 832
12.5.6.1 Ambiguity in a “Detection” of Extraterrestrial Life .................................................................................. 832
12.5.6.2 The Potential for Unidentified Biohazards................................................................................................. 832
12.5.6.3 Quarantine and Settlement......................................................................................................................... 833
12.5.7 Summary and Conclusions ......................................................................................................................................... 833
References ................................................................................................................................................................................. 833

12.5.1 INTRODUCTION
12.5.1.1 OVERVIEW OF PLANETARYPROTECTION CONSIDERATIONSPrevious sections of this book have reviewed in great detail thehistorical and ongoing efforts to understand the origin and evolution of life on Earth, as well as the potential for life to exist on
other planets. One of the critical questions in searching for life
elsewhere is to ensure that contamination from Earth does notinterfere with detection of extraterrestrial signals—this could
lead to interpretation of results that are either “false-positive”(e.g., reports of fossil Mars life in the meteorite ALH84001
that was subsequently shown to be abiotic; see Steele et al.
2010) or “false-negative” (e.g., failure to identify indicationsof Mars organic compounds in data from NASA’s Viking missions to Mars; see Glavin et al., 2013; Freissinet et al., 2015).
The potential for Earth contamination to interfere with scientific investigations of other planetary objects and the need
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820

for international standards to reduce this risk were recognizedinternationally around the launch of Sputnik (e.g., Committee
on Contamination by Extraterrestrial Exploration [CETEX],
1958, 1959). Very rapidly thereafter, guidelines and practices
were put in place to prevent contamination; these are collectively known today as “planetary protection,” as describedin detail by Meltzer (2011). Planetary protection policy andguidelines are founded in the best available scientific knowledge and maintained by the International Council for Scienceto provide consensus standards, for use by all countries andspace exploration activities, as part of complying with United
Nations (UN) treaty obligations. The policy and guidelines are
regularly updated to reflect new scientific discoveries, following a process that continues to this day.

12.5.1.2 RELATIONSHIP TO ASTROBIOLOGYAND PLANETARY EXPLORATION
All missions coming in close proximity to other planets
have a potential to introduce Earth contamination, which
could reduce confidence in scientific conclusions relating to
extraterrestrial life detection. In addition, the introductionof Earth organisms capable of surviving for long periods ina dormant state could put in jeopardy future human goals
such as settlement or terraforming, which are entirely outside
the scope of near-term scientific missions or other exploration activities. Control of Earth contamination on planetary
spacecraft is a technological challenge that has been surmounted on multiple occasions, most notably during NASA’s
AQ 1 Viking program in the 1970s (Daspit et al., 1988) and theEuropean Space Agency (ESA’s) ExoMars missions ongoing
today. “Forward contamination” is the term used to describe
these processes, which have risks that can be determinedand quantified—at least to the extent that we understand thecapabilities of Earth organisms and non-living contamination to be present on spacecraft, and persist after introduction
AQ 2 to planetary environments.
In contrast, potential risks resulting from the introductionof extraterrestrial organisms into the environment of the Earth,termed “backward contamination,” are entirely unknown andcurrently unquantifiable, because, to date, we have no evidence regarding the characteristics of possible extraterrestrial
life and thus no basis to assess pathogenicity or ecologicalconsequences. From a policy and regulatory standpoint, these
uncertainties about the actual risks of backward contamination are compounded by challenges associated with detecting extraterrestrial life, if it is present. The two Viking andthe Mars Science Laboratory (MSL) missions to Mars carriedsensitive instruments to detect metabolic activity (Viking) ororganic compounds (Viking and MSL) on Mars (e.g., Glavin
et al., 2013; Freissinet et al., 2015). Each of these missions
returned data indicating levels of Earth contamination thatexceeded detection limits for Mars organics, and these data
were interpreted as non-detections of Mars life—however,in the case of the Viking Life Detection Package, one of theprincipal investigators still publishes papers disputing thisconclusion (e.g., DiGregorio et al., 1997).

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In 1964, a decade prior to the Viking missions, the US
Space Science Board (SSB) was asked to evaluate backward
contamination issues for NASA’s Apollo program and futureMars missions. It noted that “negative findings could provide a sense of security which might well be false” (Space
Science Board [SSB], 1964). The possibility that extraterrestrial organisms could be hazardous, either to the environmentof the Earth or to humans directly, makes detecting themat very high sensitivity a primary concern for ensuring thesafety of the Earth.

12.5.1.3 INTERFACES WITH WIDER SOCIETY
On Earth, humans have a long history of transporting biological organisms from one location to another, which has oftencaused major disease outbreaks and/or ecosystem disruption,
as reviewed in Mann (2011) and many others. It is not knowable, until we have an example of extraterrestrial life, whether
that life could become pathogenic or disrupt the ecosystems
that humans rely on. In contrast, we do know that Earth organisms inadvertently transported on spacecraft could interferewith future objectives of human settlers, as they have done on
Earth in the past. Avoiding the accidental transport of Earthorganisms, before decisions are made to introduce them, isa long-term concern for planetary protection, because one
single release of a self-replicating entity into a habitable environment can engender a persistent population and thus cause
permanent contamination.
For the reasons mentioned above, it is essential to address
planetary protection at the highest levels of global societal
decision-making, which for 60 years has been done via the
UN and the International Council for Science. In addition, toensure that one bad actor does not cause permanent damage toeveryone, individual nations have obligations under the 1967
Outer Space Treaty to take appropriate measures to ensurethat all exploration of other planets carried out under theirauspices, whether governmental or private/commercial, follows the same guidelines. Space exploration is the first effort
in human history for which we, as a global society, have recognized the potential risks of contamination before it happened, and planetary protection is the first time humanity as a
species has taken responsible steps to prevent it.
AQ 3

12.5.2 PLANETARY PROTECTION:
DEFINITION AND SCOPE
Planetary protection covers explicitly the search for extraterrestrial life and also the potential for Earth life to interferewith future human objectives: the focus of planetary protection is exclusively on biological contamination and does
not address other kinds of contamination such as radiationor physical detritus. Due to the very high level of concern
for protecting the Earth on which we all live, relative to themore limited concern about contaminating other planets, theguidelines and policy for planetary protection are divided,
conceptually, on the basis of whether spacecraft are only traveling outward to other planetary bodies and therefore could

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Planetary Protection

cause forward contamination, or whether there is an expectation that hardware will return back to Earth, possibly carrying extraterrestrial material, which could release backward
contamination.

12.5.2.1 FORWARD CONTAMINATION CONCERNSSpacecraft traveling to another planetary body (moon, asteroid, comet, etc.) have the potential to cause forward contamination by depositing organic material and/or organisms
from Earth onto the target object. Forward contamination
is of concern for planetary protection only to the extent that
contaminants could interfere with scientific or other humanobjectives at the target object. The vast majority of objects
in the solar system are known to support conditions inhospitable to all Earth life (e.g., no atmosphere, too irradiated,
and too dry), and therefore, spacecrafts going to them are notcontrolled to prevent introduction of Earth organisms. To theextent that a non-habitable object is of scientific interest forunderstanding the origin and evolution of life in the solar system, which involves studying whatever organic compounds
could be present, a mission may be required to provide a listof materials present on the spacecraft and to report locations
where spacecraft hardware is left at end of mission. Missions
going to non-habitable targets are required to provide only astraightforward set of documentation about hardware composition, spacecraft operations, and final disposition.
In contrast, when a planetary body has the potential toprovide a habitat for Earth organisms, spacecraft traveling tothem are required to avoid introducing Earth organisms into
habitats: this involves applying very strict decontamination
procedures to hardware that could introduce Earth organisms and also (or instead) avoiding contact of contaminatedhardware with potentially habitable environments. Currently,
three solar system objects are of concern for contamination
by Earth life: the planet Mars, and the moons Europa around
Jupiter and Enceladus around Saturn. Other planetary bodies may be added to this list as additional potential habitats
are identified, and requirements to prevent contamination ofthem should be put in place. Missions going to habitable targets are required, as part of as part of mission formulation, to
submit and receive approval for detailed plans that describe
proposed decontamination procedures; during hardware
assembly and launch operations, they will undergo regularinspections and extensive reviews to confirm complianceprior to launch, and after launch, they continue to ensure contamination avoidance during spacecraft operations, as wellas to provide information about relevant research findings
and report final hardware disposition.

12.5.2.2 BACKWARD CONTAMINATION CONCERNS
When spacecraft hardware is being brought back to Earth after
contact with another planetary body, it is of primary concern
to ensure the safety of the Earth’s biosphere and everythingthat lives in it. Again, the focus is on biological contamination, so the same conceptual distinction is made relating toK33392_C012_05.indd 821

habitability and the potential for extraterrestrial life—definedas biochemistries that could function in the surface physicalenvironment (temperature, pressure, etc.) of Earth—with very
different levels of concern around preventing release of material from “potentially habitable” versus “non-habitable” target objects. Missions returning from all non-habitable target
objects, including the Earth’s Moon and near-Earth asteroids,
follow planetary protection guidelines to provide documentation of the target’s non-habitability during mission planningphases and receive no further planetary protection requirements once appropriate review is completed.
As with forward contamination, restrictions are only
imposed on spacecraft returning from objects that mighthost extraterrestrial life, which is by definition consideredbiohazardous until tests demonstrate otherwise—currently,
this includes the three “potentially habitable” objects: Mars,
Europa, and Enceladus. If other solar system objects arefound, in future, to host physical conditions that could support
biochemistries also potentially active on Earth, then theseother objects would be added to the short list requiring stringent precautions for sample return. Missions sending hardware intended for return from potentially habitable targets
are required stringently to limit contamination from Earththat could interfere with detecting extraterrestrial life, as well
as all requirements appropriate to the particular outboundmission—these missions are also required to maintain anarchive and detailed record of potential Earth contaminants
and the provenance of samples collected, in a format that canbe provided to a pre-return “Earth Safety” review process thatwill be carried out at international level (e.g., Haltigin et al.
AQ 4
2018; Kminek et al., 2018).
Appropriate documentation on the return status of all missions also needs to be carried through whatever local/national
approval processes apply to a re-entry event into the Earth’s
atmosphere.

12.5.2.3 INTERNATIONAL, NATIONAL, AND AGENCYLEVEL OBLIGATIONS AND RESPONSIBILITIESThe current set of accepted international consensus guidelines on how to implement planetary protection is held bya permanent committee of the International Council for
Science, the Committee on Space Research (COSPAR)(Kminek et al., 2017). The 1967 Outer Space Treaty, moreaccurately the “United Nations Treaty on Principles Governing
the Activities of States in the Exploration and Use of Outer
Space, including the Moon and Other Celestial Bodies,” is the
major international agreement governing how treaty signatories(“States Parties to the Treaty”) go about exploring and using
outer space (United Nations [UN], 1966). This treaty has beensigned by all countries involved or interested in space exploration, numbering over 100 and including North Korea (United
Nations [UN], 2018).
The United Nations Committee on the Peaceful Uses ofOuter Space (UN-COPUOS) is the committee of the United
Nations in which discussion of matters related to the treaty
takes place. The UN-COPUOS, in its 60th meeting report to

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AQ 5 the UN General Assembly in 2017, “noted the long-standingrole of COSPAR in maintaining the planetary protection
policy as a reference standard for spacefaring nations andin guiding compliance with article IX of the Outer Space
Treaty” (United Nations Committee on the Peaceful Uses ofOuter Space [UN-COPUOS], 2017). This recognition reiterates the role that COSPAR has played over the 60 years
AQ 6 since its creation in 1957 (described below and reviewed inMeltzer, 2011).
States parties to the Outer Space Treaty, by signing andratifying the document, agree to abide by all 17 treaty articles,
including Article IX which reads, in part:“States Parties to the Treaty shall pursue studies of outerspace, including the moon and other celestial bodies, andconduct exploration of them so as to avoid their harmful contamination and also adverse changes in the environment of
the Earth resulting from the introduction of extraterrestrial
matter and, where necessary, shall adopt appropriate measures for this purpose.”

The COSPAR planetary protection policy addresses “harmful contamination” in the context of forward contamination and “adverse changes in the environment of the earth
resulting from the introduction of extraterrestrial matter” inthe context of backward contamination. As noted previously,
other forms of contamination or environmental damage are
not addressed by the COSPAR planetary protection policy or
guidelines.
Other articles of the Outer Space Treaty impose additional
obligations on States Parties to the treaty that are relevant toplanetary protection. Article VI requires that:“States Parties to the Treaty shall bear international responsibility for national activities in outer space, including the moonand other celestial bodies, whether such activities are carriedon by governmental agencies or by non-governmental entities.”

Further, States Parties must assure that:“The activities of non-governmental entities in outer space,including the moon and other celestial bodies, shall requireauthorization and continuing supervision by the appropriateState Party to the Treaty.”

In general, each State Party to the Outer Space Treaty has
assigned the responsibility to ensure compliance with international planetary protection guidelines to their national
space agency, which, in some cases, also requires cooperation with other national agencies that regulate activities
within the Earth’s atmosphere. In the case of the ESA, which
is a regional organization with multiple national members,
the responsibility of each State Party to ensure compliancewith planetary protection policy and guidelines, for ESA
missions in which they participate, has been transferred to
ESA. Individual States Parties are also responsible for developing internal processes to provide the required “authorization and continuing supervision” of the actions of their
non-governmental entities.

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12.5.3 A BRIEF HISTORY OF
PLANETARY PROTECTION
12.5.3.1 EARLY CONCERNS
Fictional accounts of interplanetary travel causing biological contamination, including ecological damage and pathogenicity (e.g., Wells, 1898), reflect historical experiencesfrom European colonialism and the Columbian Expansion.
For related historical reasons, “planetary quarantine” wasthe term used instead of “planetary protection” prior to themid-1980s, but the practices and precedents are identical.
Planetary protection as a practice began after World War
II, with concerns expressed by scientists involved in organizing the 1957–1958 International Geophysical Year. In
preparatory discussions, the international scientific community recognized that advances in rocketry would soon
permit artificial satellites to be launched from Earth to the
Earth’s Moon and other planets. Concerns about potential biological contamination were first raised at the 7thInternational Astronautical Congress held in Rome, Italy,
in September 1956 (Phillips, 1974; Meltzer, 2011). Boththe United States (US) and the Soviet Union (USSR)
announced plans to launch Earth-orbiting satellites forscientific research purposes, with the USSR launching
two Sputnik satellites in 1957 and the US launching the
Explorer and Vanguard satellites in 1958, as reviewed in
Doyle and Skoog (2012).
Starting in 1958, with the formation of UN-COPUOS
and COSPAR, as well as multiple national space agencies,
extensive discussion of how to prevent biological contamination by planetary spacecraft took place in the international community, including Europe, the US, and the USSR,
facilitated by interactions associated with the International
Geophysical Year (e.g., Committee on Contamination by
Extraterrestrial Exploration [CETEX], 1958, 1959). Within
the US, the National Academy of Sciences (NAS) convened
a working group known as the West Coast Committee on
Extraterrestrial Exploration (WESTEX), chaired by Melvin
Calvin and including Joshua Lederberg and the graduate
student Carl Sagan, that supported the NAS’ newly formed
Space Science Board as well as COSPAR. Discussions held
during WESTEX meetings, as documented in their final
report and appendices (Space Science Board [SSB], 1959),
addressed all the concerns of planetary protection that
inform policy today, emphasizing both their historical basis
and global scope.
Statements made in 1959 by this committee, on the topicof transporting extraterrestrial materials to Earth, are surprisingly pertinent in providing clarity to current debates:“We know of many unhappy examples of biological competition from the introduction of new organisms into freshniches—e.g., many insect pests in the US; rabbits and prickly
pear in Australia, smallpox into the New World, and syphilis into Europe. Even the relatively limited damage of theseincidents should not be duplicated as a byproduct of spaceresearch.” (WESTEX Report, pg. 17)

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823Planetary Protection“Finally, it may be remarked that the task of evaluating
the potential hazard of a planetary biota will be multiplied
if this has to be isolated from organisms inadvertently transferred from Earth.” (WESTEX Report, pg. 18)

12.5.3.2 EVOLUTION OF PLANETARY PROTECTION
POLICY AND GUIDELINES
During the late 1950s and early 1960s, frequent discussions
were held in the international arena that informed the development of guidelines on how to respond to policy-level concerns
about planetary contamination and potential consequences
for scientific research and other human endeavors (reviewed
in Phillips, 1974; Meltzer, 2011). The need for a risk-based
approach that included the careful sterilization of spacecraft
hardware was recognized very early, and methods for accomplishing this were proposed and evaluated (e.g., Space Science
Board [SSB], 1959, 1964). Early missions implemented an
approach based on a “probability of contamination” model,
with information gained from each mission, leading to refinements in policy and guidelines over time.
In the 1980s, COSPAR accepted a conceptual shift in
the formulation of planetary protection policy, movingfrom an explicit risk-based probabilistic approach to the “by
exception” approach used today (COSPAR internal decision
memo No. 7/84, accepting the proposals in DeVincenzi et al.,1983). This shift responded to accumulated scientific data,
showing that most solar system objects were not contaminable
by Earth life and, therefore, by inference, were also unlikely
to host extraterrestrial life that could be biohazardous to the
Earth. Four categories of possible outbound missions were
described, as in Table 12.5.1, determined by the level of interest in the target object for understanding the origin and evolution of life and also the mission operations to be performed.
Missions to objects not of concern for understanding theorigin and evolution of life are assigned Planetary Protection
Category I, with no further documentation or other requirements. Missions to objects that do not provide natural
habitats for Earth life but that could retain organic and prebiotic compounds of scientific interest are assigned PlanetaryProtection Category II, and limited documentation of mission
operations is required—this includes the vast majority solar
system objects. Missions to solar system objects that could
provide habitats for Earth life—as noted previously and currently include Mars, Europa, and Enceladus—are assigned
Planetary Protection Category III if hardware is not intended
to contact the target object (flyby and orbiter missions) andassigned Planetary Protection Category IV if hardware isplanned to contact the target (probe and lander missions).
Because of the considerable interest in Mars as a target ofhuman exploration beyond purely scientific investigations,and the more extensive information available about the planet,
Planetary Protection Category IV landed missions to Mars
are further divided on the basis of landing site and mission
objectives, as described in the “future missions” section later.
In addition, a fifth category of “Earth Return” missions wasestablished, recognizing explicitly the much higher priority
placed on protecting the biosphere of the Earth than elsewhere, as noted in Table 12.5.1. This Earth Return category,
Planetary Protection Category V, is divided into “Restricted”
and “Unrestricted” Earth Return, determined by evaluating scientific data supporting the hypothesis that samples to be brought
to Earth contain no extraterrestrial life, which is by definition
considered biohazardous. For most solar system objects, thisis accomplished by responding to the six questions listed inTable 12.5.2, about conditions on those objects and the natural
influx of material to Earth.
When data are inconclusive or support the presence of possible habitats, as is true for Mars, Europa, and Enceladus, thena designation of Planetary Protection Category V “Restricted
Earth Return” is given. Planetary Protection Category V“Restricted Earth Return” applies to all missions involvedin a sample return effort—this is to ensure that informationneeded to support the pre-return Earth safety analysis andpost-return biohazard test protocol is captured and retained byearly outbound missions as well as the final return leg. Eachmission carrying hardware intended for possible future returnto Earth, including missions that emplace hardware possibly tobe retrieved by future mission activities, also receives requirements appropriate to that particular orbiter or lander mission.

TABLE 12.5.1
Planetary Protection Mission Categories
Planet Priority
A
B

C

All

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Not of direct interest for understanding the process of chemical evolution.
No protection of such planets is warranted.
Of significant interest relative to the process of chemical evolution, but
only a remote chance that contamination by spacecraft could jeopardize
future exploration. Documentation is required.
Of significant interest relative to the process of chemical evolution and/or
the origin of life or for which scientific opinion provides a significant
chance of contamination that could jeopardize a future biologicalexperiment. Substantial documentation and mitigation are required.
Any solar system body

Mission Type

Mission Category

Any

I

Any

II

Flyby, Orbiter
Lander, Probe

III
IV

Earth Return “Restricted”
or “Unrestricted”

V

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824

TABLE 12.5.2
Six Questions for Restricted Earth Return
1. Does the preponderance of scientific evidence indicate that there wasnever liquid water in or on the target body?
2. Does the preponderance of scientific evidence indicate thatmetabolically useful energy sources were never present?
3. Does the preponderance of scientific evidence indicate that there wasnever sufficient organic matter (or CO2 or carbonates and an appropriate
source of reducing equivalents) in or on the target body to support life?
4. Does the preponderance of scientific evidence indicate that
subsequent to the disappearance of liquid water, the target body has
been subjected to extreme temperatures (i.e., >160°C)?
5. Does the preponderance of scientific evidence indicate that there is or
was sufficient radiation for biological sterilization of terrestrial
life-forms?
6. Does the preponderance of scientific evidence indicate that there has
been a natural influx to Earth, for example, via meteorites, of material
equivalent to a sample returned from the target body?

12.5.3.3 PLANETARY PROTECTION POLICYAPPLIED TO EARLY PROGRAMS
12.5.3.3.1 Soviet Decontamination Efforts
Soviet scientists were involved, from the earliest international discussions, in raising concerns relevant to planetary
protection, and it was reported to the international community that early Soviet lunar missions did comply with thenascent guidelines being developed by COSPAR. Theseannouncements had significant influence on decisions
made within the US to ensure that early NASA missions
would be decontaminated, as documented in a memo dated
September 14, 1959, from the executive director of the SSB,
Hugh Odishaw, to the first NASA Administrator T. Keith
Glennan (Space Science Board [SSB], 1959, pg. 84), and also
in the final report of WESTEX, which states: “We applaud
the respect for these considerations on the part of the USSRin the light of Academician Topchiev’s announcement that
Lunik-II has been decontaminated.” (Space Science Board[SSB], 1959, pg. 13)
Throughout the 1960s, it was reported in public that Soviet
spacecraft sent to Mars and Venus had been “sterilized,” butthere was significant uncertainty in the West as to what thisactually meant, as reviewed in Meltzer (2011). Questions wereraised, in the international community, about the benefit of
implementing stringent sterilization protocols on some spacecraft, if other spacecraft had already delivered Earth organisms to the same target—as if a single contamination event
would render completely useless all subsequent efforts tolimit additional contamination. This is a little like someone
asking “Why should we keep brushing our teeth, after we’ve
eaten our first candy-bar?”
12.5.3.3.2 Ranger
A number of NASA’s early missions were managed by the Jet
Propulsion Lab (JPL) in Pasadena, California, which, along with

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all other NASA facilities, was instructed to ensure appropriate
sterilization of planetary spacecraft, in October 1959, following
the recommendations from the SSB mentioned previously (seeHall, 1977 for details). Prior to this, JPL had established a program to develop methods for spacecraft sterilization, which presented a paper at the 10th International Astronautical Congress,
containing the statement “Sterilizing space probes is an engineering nuisance, however, the same ordeal has confronted
surgical crews for quite some time. In both instances, anticipation of the task is necessary.” (Davies and Comuntzis, 1959,
included in Space Science Board [SSB], 1959). Paradoxically,at the same time, JPL also began designing a multi-purpose
planetary spacecraft bus, called “Vega,” that did not include any
sterilization-tolerance requirements in the design constraints.
This design was adopted for use in the Ranger program in
1959, by which time it had already undergone considerable
preliminary testing and refinement (Hall, 1977). In 1960, JPL
staff proposed a sterilization protocol that involved subjecting
components, subsystems, and the assembled spacecraft system to 125°C before shipment to the launch site, with a final
ethylene oxide gas treatment applied at the launch site to eliminate organisms that might have recontaminated spacecraft
surfaces during transport and launch preparations. Despite
the plan to apply a system-level heat treatment, design constraints for the Ranger program, including those provided to
subcontractors and instrument contributors, did not include
heat tolerance among the requirements, and very little testing was done, during development of Ranger spacecraft hardware, to evaluate the tolerances of spacecraft components andsubsystems to heat treatment.
Despite the October 1959 memo requiring spacecraft
sterilization, and associated 1960 protocol, only a few of thecomponents selected for the Ranger spacecraft, and none of
the early engineering or flight models, were tested for compatibility with heat sterilization treatment. The first hardware toundergo a heat sterilization protocol was the flight model of thefirst lander spacecraft, Ranger 3. Multiple materials’ incompatibilities and failed components were identified during subsequent testing, which required extensive re-work. At the time,
JPL reported “Although no failures are directly traceable toheat damage, it is felt that heat sterilization does shorten the
expected life of electronic components” (Hall, 1977, pg. 124).
Today, military specifications for high-reliability hardware
require an operational high-temperature burn-in phase,to eliminate defective components at risk for early failure(MIL-STD-810G, 2008).
After the launch of Ranger 3, which included a prelaunch ethylene oxide gas treatment (tolerance to which was
also not mentioned in design constraints), the spacecraft“performed flawlessly” (Hall, 1977, pg. 147), but incorrectcommands transmitted from ground control caused thespacecraft to lose contact, without accomplishing any mission objectives other than impact on the Moon. Despite thissuccessful performance, the reaction from Ranger project
managers was to attribute the failure to heat sterilization(Hall, 1977, pg. 125):

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825Planetary Protection“Although lacking firm evidence that this requirement caused
the equipment failures, JPL now requested and received morewaivers from NASA Headquarters on heat sterilizing certain
crucial components.”

Rangers 4 and 5 underwent only partial heat sterilization
treatments, though they were subjected to pre-launch ethyleneoxide gas because this was not considered a risk to spacecraft
hardware—yet both missions were unsuccessful, with failuresin spacecraft bus control systems despite electronic components having been exempted from heat treatment.
In 1962, after the failure of Ranger 5, the program was
extensively reorganized, with new management and a muchstrengthened quality-assurance program, and the program
received approval to cease all sterilization treatments. In
1963, a few months prior to the planned launch of Ranger 6,
it was discovered that a particular type of diode, used by thehundreds throughout each of the Ranger spacecraft, was often
defective and susceptible to shorting in microgravity, “withpotentially disastrous consequences” (Hall, 1977, pg 197).
Potentially defective components were replaced extensivelyin Rangers 6 through 9, with much better quality control on
the replacements—even so, the cameras on the Ranger 6
spacecraft did not function, though the rest of the mission was
accomplished successfully. Rangers 7, 8, and 9 were considered to be fully successful and returned imagery that was ofconsiderable interested to both the scientific community andthe general public, as well as useful to the Apollo program forlanding site selection.
The Ranger program was instrumental in establishingprocesses in space mission formulation that balance scientific and engineering concerns, as well as quality-control
programs and interfaces for project management, that havesubsequently become widely implemented on NASA’s robotic
missions. The influence of the Ranger program on the development (or lack thereof) of standard approaches for spacecraft
sterilization is not so well recognized but is still considerable.
12.5.3.3.3 Apollo
The Apollo program remains the most complex effort in space
exploration attempted prior to 2018, involving astronauts
landing on another planetary body and returning to Earthwith samples, as well as both samples and astronauts being
subject to isolating containment and analytical and biohazard testing after return to Earth. Apollo was, applying current
planetary protection policy, a Planetary Protection Category
V Restricted Earth Return campaign, including all the additional health and safety concerns associated with humanspaceflight. The history of the Apollo program has been covered extensively elsewhere (e.g., Launius, 1994), so only two
aspects of the Apollo program are mentioned here, as being ofparticular relevance to planetary protection.
In the words of US President Kennedy, the Apollo program was established for “landing a man on the moon andreturning him safely to earth”—more for purposes of politicaland technological positioning than for scientific investigation

K33392_C012_05.indd 825(Launius, 1994). Even before the inception of the Apollo
program, it was understood that the return of astronauts andextraterrestrial materials back to Earth had the potential tointroduce extraterrestrial biohazards, as reviewed previously
and by Meltzer (2011), and the US Government recognizedthat these risks needed to be controlled. In 1963, after questions were asked about backward contamination in Congress(Meltzer 2011), President Kennedy signed National Security
Action Memo 235, on “Large-Scale Scientific or TechnologicalExperiments with Possible Adverse Environmental Effects”(JFK Library, 1993), which established a process that requiredpresidential approval prior to conducting any such experiments, in consultation with the NAS and other relevant federal agencies (e.g., the State Department). In particular:“Experiments which by their nature could result in domestic or foreign allegations that they might have such effects
will be included in this category even though the sponsoring agency feels confident that such allegations would in factprove to be unfounded.”and“international scientific bodies or intergovernmental organizations may be consulted in the case of those experiments thatmight have adverse environmental effects beyond the U.S.”

This memo, declassified in 1993, was applicable both to US
nuclear testing activities and to the Apollo program.
Following public expressions of concern about backward contamination, NASA consulted with the US Public
Health Service, which assigned a liaison officer to support
the development of a “quarantine” program. This resulted
in the formation of an “Interagency Committee on Back
Contamination” (ICBC), chartered to provide oversight ofboth astronaut quarantine and curation of lunar materials.
The committee included the three US regulatory agencies
covering public health, agriculture, and the environment, as
well as two additional “interested agencies”: the NAS andNASA. A formal interagency agreement was established that
required high-level interagency consultation prior to acting
on any decision that was not “in accordance with the unanimous recommendation of the agencies represented on theInteragency Committee on Back Contamination.” NASA is
not a regulatory agency, so this structure ensured that theregulatory agencies would exert effective oversight, eventhough over half the individual members of the ICBC wereNASA staff (Radley and Rosen, 1969).
The interagency coordination framework that was established during the Apollo program, which was founded on
the best-available scientific advice and included the regulatory agencies responsible for ensuring the health and safetyof humans, animals, and agricultural activities, and the wider
environment, was sound. In practice, the ICBC did perform
oversight of the Apollo program’s sample return activities
and issued determinations regarding astronaut quarantine andbiohazard testing of lunar materials, including termination

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of the quarantine program after Apollo 14. However, it wasvery fortunate that lunar samples, in fact, are not biohazardous to astronauts or the Earth, because the implementation ofquarantine measures during the Apollo program would nothave been adequate to prevent release. Reluctance on the partof those responsible for implementing the program was motivated by disputes over jurisdiction and authority, cost concerns, and a rather widespread perception within the space
exploration community that precautions were unnecessary, as
reviewed in Meltzer (2011). Many very valuable lessons canbe learned from the Apollo program, both on practices thatwere surprisingly foresighted, and should be replicated, andon aspects of sample return and post-return operations thatwould benefit from improvement.
One rather famous example, which would be good not torepeat, involves biological analyses performed on the Surveyor
3 camera, which were claimed to show survival of Earthorganisms after traveling round trip to the Moon (Rummel
et al., 2011). The Surveyor robotic mission landed on the Moon
in 1967 and was not subject to decontamination proceduresfor planetary protection. The Apollo 12 mission landed near
the Surveyor 3 site in 1969, and astronauts collected hardware
from the Surveyor 3 lander spacecraft, including a camera,
for return to Earth. The Apollo 12 astronauts and other lunar
samples that had been collected were subject to quarantine
and containment procedures; in contrast, the camera from
Surveyor 3 was placed in a laminar flow hood and subjected
to biological sampling. The organism Streptococcus mitis,
commonly found in the human respiratory tract and rapidly
killed by desiccation, was the only organism isolated fromthe camera and was found in only one sample collected verylate in the sampling period. The sampling process was filmed,
and these films document that the “sterile technique” practices used by the technicians collecting samples would not,today, be considered adequate to maintain sterile culture conditions. In addition, a photographer leaned into the hood andtook close-up still images, just prior to biological sampling,of the location on the Surveyor 3 camera, from which the
S. mitis organism was collected. The appearance of S. mitis
in cultures from the Surveyor 3 camera prompted a review,
during which the Surveyor 3 spacecraft engineering model
was found possibly to have been contaminated by S. mitis.
Following this observation, it was concluded that the organism collected after return must have survived the round-trip
travel between the Earth and the Moon, including years of
exposure on the lunar surface.
Several logical fallacies, of concern to planetary protection, can be identified in this procession of events, which
would be better avoided in the future. First, given that lunar
quarantine procedures were supposed to be in place, how is
it that the Surveyor 3 camera was sampled in what was effectively a shirt-sleeve environment, with a photographer present
in street clothes rather than within containment? Second, theconclusion that a desiccation-sensitive organism must havesurvived several years of exposure to hard vacuum should haverequired some additional supporting data beyond the merely
AQ 7 circumstantial—the principle “Extraordinary claims require

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extraordinary evidence” does apply. Finally, the collection of
unsterilized hardware by astronauts, who are subject to quarantine, adds the risk that they could be exposed to pathogenic
Earth organisms from the collected hardware, possibly invalidating the purpose of a quarantine altogether. Streptococcus
mitis, though mostly harmless, is a facultative human pathogen that can cause infective endocarditis—which was not, inthe 1960s, an easy disease to diagnose. The trajectory of theApollo program, and the future of human spaceflight, might
have been quite different if, during quarantine, the Apollo 12
astronauts had come down with fever, bruising, exhaustion,
stroke, and possibly heart or kidney failure.
12.5.3.3.4 Viking
If one early robotic exploration program stands out from allothers for effective planetary protection compliance, that isthe Viking program, which in the 1970s sent NASA’s firstlander missions to Mars (Daspit et al., 1988). The Viking
program was managed by NASA Langley Spaceflight Centerin Virginia, with prime contractor support from the Martin
Marietta Corporation, and the lander spacecraft carried scientific instruments contributed by several academic institutions
as well as other US government facilities. Each of the two
Viking landers was transported to Mars by a Viking orbiter
spacecraft, which carried replicate sets of scientific experiments. The two Viking landers returned the first meteorological, physical, and seismological measurements, as well as
performed both metabolism- and chemistry-based life detection experiments, from two locations on the surface of Mars
(Ezell and Ezell, 1984).
The Viking landers carried a suite of instruments designed
to detect chemical constituents of possible Martian organisms,
as well as metabolic indicators of possible Mars life. Both ofthese instrument payloads received cleanliness requirementsthat were more stringent than the rest of the Viking lander
spacecraft (Daspit et al., 1988), to protect the integrity of thescientific results obtained from them. The chemistry-based
experiment utilized a gas chromatograph-mass spectrometer(GC-MS) instrument to measure gases that evolved as Martian
regolith was heated, results from which were interpreted at thetime to indicate the presence of cleaning fluids used before
launch from Earth. However, in 2017, it was reported that
low-abundance peaks from the Viking GC-MS data indicate
the presence of compounds, in the Viking samples, that were
definitively identified by the Curiosity rover’s Sample Analysis
at Mars instrument as being Martian in origin (e.g., Glavin
et al., 2013; Freissinet et al., 2015). The metabolic experiments
included several culture cells that provided conditions predicted
to support growth of Martian organisms, as well as the ability to heat samples of Mars regolith to temperatures expected
to inactivate any organisms, as discussed in DiGregorio et al.
(1997). The results from this suite of experiments, known as
the “Life Detection Package,” definitely detected heat-labile
chemical reactivity but were inconclusive as to whether thiswas consistent with biological metabolism. At the time,
because the GS-MS instrument data were interpreted to indicate the absence of organic material in the regolith samples,

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Planetary Protection

AQ 8

AQ 9

the Viking results were interpreted as a failure to detecting
Mars life, although this interpretation has subsequently beenquestioned (e.g., Navarro-Gonzalez et al., 2006).
The Viking program undertook the most stringent
implementation of planetary protection requirements everattempted, involving component or subsystem-level heat
treatment to reduce microbial populations present inside theitems or materials; careful cleaning of hardware surfaces
to reduce the levels of heat-resistant microbes to fewer than
300 per square meter of spacecraft surface; packaging of theentire assembled lander and heatshield into a “bioshield” thatwas overpressured through launch, to prevent recontamination after heat microbial reduction; and finally, shortly prior
to launch, a full-system heat microbial reduction treatment of
the lander spacecraft inside the bioshield for over 40 hours at
112°C, which was demonstrated to reduce the levels of viablemicrobial contamination on lander surfaces by four orders ofmagnitude. The key to the successful implementation of thiseffort was the complete acceptance of planetary protection
requirements on the part of project staff, including the ProjectManager James Martin and the Project Scientist Gerald
Soffen, both at NASA Langley, with strong support from program staff at NASA Headquarters (Daspit et al., 1988).
From the very beginning of the program, planetary protection requirements were fully captured in the design constraints for the landed hardware and integrated with controls
on approved parts and materials, as well as testing, assembly,
and operational procedures, that were followed by almost all
hardware contributors (see below). Viking Program staff at
Langley were well-educated about planetary protection, having consulted with members of WESTEX, and studied heatsterilization of hardware since 1964 (Ezell and Ezell, 1984) as
well as attended meetings of the planetary protection advisorycommittee for several years prior to the start of the programin 1969 (Daspit et al., 1988). Although questions were raised
about the need for heat microbial reduction prior to the startof the Viking program, once that was confirmed, on the basisof life-detection science contamination concerns as well asinternational policy considerations, planetary protection was
managed as just another element required for project success.
From the start, it was recognized that electronic components and other spacecraft materials were not necessarily
pre-qualified to tolerate temperatures planned for the final
system-level heat microbial reduction, so the majority of partsand materials was acquired and tested in bulk. Issues related
to heat treatments appeared on the project manager’s “Top10 Concerns” lists early during the program (Ezell and Ezell,
1984), but all of these were retired, by appropriate qualification, substitution, or process modification, by mid-1972, prior
to the assembly of spacecraft hardware. During hardware
assembly, an extensive model testing program was carried out;
it included evaluation of heat tolerance, starting with smaller
and then larger subsystems and continuing with full lander
system qualification models. No significant issues were foundafter both of the flight systems underwent the full-system heatmicrobial reduction, validating the general assessment by
Viking managers that the testing and qualification program

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significantly reduced risk and increased the reliability of thespacecraft (Daspit et al., 1988).
It is certainly true that the Viking requirement for heat tolerance required extensive component testing and replacementof susceptible parts and materials in heritage hardware, whichmight appear to increase program cost. However, multiple
Viking managers observe that the bulk purchases and extensive testing program also had cost benefits, in reducing theneed to evaluate components case by case, and then re-worksubsystems after they failed. For new hardware subsystems, AQ 10
requirements for heat tolerance could be addressed during
the design phases and if done well should not have increased
cost significantly, beyond the difference in component prices(Daspit et al., 1988). When these design constraints were notaddressed adequately, both cost and schedule slips were theresult, as demonstrated for the camera system originally contracted to the company TRW (Ezell and Ezell, 1984).
AQ 11
In the case of the GC-MS instrument, that was contributedby JPL, heat-tolerance requirements were not addressed effectively during the design phases, and a number of problems
with this instrument were reported. The GC-MS instrumenton the Viking 2 lander, which was located at higher latitude
and therefore experienced greater thermal cycling, failed during the extended mission phase, with one engineer on thatteam attributing the problem to weaknesses induced by the
pre-launch full-system heat microbial reduction. However,other Viking managers noted that the GC-MS team was reluctant to accept the heat-tolerance requirements, to a greater
extent than other hardware providers (see Daspit et al., 1988).
It is possible that this reluctance on the part of some JPL engineers to embrace heat sterilization is influenced by corporate
memory of the Ranger program discussed previously.
It is sometimes claimed that planetary protection required
10% of the total Viking program budget, with an implicationthat this is an unreasonable cost for a mission that both protects
the target of exploration and performs experiments searching for extraterrestrial life (e.g., Fairén et al. 2018). However,as described previously, it is not actually possible to pull out asubset of the Viking expenditures and label it as “planetary protection,” because implementation was so completely integrated
into overall project management. It is more relevant, for students of astrobiology, to understand that the total Viking program budget was about $1 billion, in 1975 dollars, with the Life
Detection Package costing $59 million and the GC-MS costing$41 million (Ezell and Ezell, 1984). These actual costs demonstrate that the two instruments on Viking, addressing researchof the greatest interest to astrobiology, together cost 20% of thetotal program budget—including all the effort to establish how
to accomplish full-system heat microbial reduction and otherassociated cleaning processes. More recent estimates of thecost to retrofit a modern Mars rover for full-system heat microbial reduction, done independently by ESA and NASA, suggest that this cost has remained at the equivalent of one major
science instrument (e.g., Rummel and Conley, 2018). Whether
the equivalent of one science instrument is a reasonable cost to
answer key research questions in astrobiology is an important
advocacy question for the astrobiology community to address.

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It is a consistent conclusion among people involved in theViking program that the requirements for full-system heatmicrobial reduction provided significant benefits to the reliability and success of the missions and was not as difficult toimplement as initially anticipated. The most important lesson
to learn from historical missions, for planetary protection in
the future, was summarized very well by the Viking ProjectManager, James Martin (quoted in Daspit et al., 1988):“There are many young people at JPL and elsewhere working
on these problems, and they are so enthused by the technologies they’re working on that they don’t realize the extent of
the impact PP and Contamination control requirements canhave or how that impact can enlarge as a problem the longer
it is neglected. The PP requirements should be expressed ina more forthright and regulatory sense, so that people aren’t
allowed to forget about it until five or ten years from now
when they suddenly discover that ‘you really can’t make awidget that you can heat.’”12.5.4 APPLICATION TO MISSIONSIN PREPARATION
12.5.4.1 OUTER PLANETS MISSIONS
12.5.4.1.1 Probability of Contamination
It has been suggested that the greatest volume of environments
providing conditions suitable for the growth of microbial life
from Earth could be in the outer solar system, in the form ofsubsurface liquid water within the moons of the giant planets,
and also any water that might remain liquid in the interiorsof Kuiper Belt objects. Such habitable environments are ofconcern for planetary protection, to the extent that the probability of introducing a single viable Earth organism into aliquid water environment must be held lower than 1 × 10 −4 per
mission, which applies to both lander and orbiter/flyby missions and must take into account spacecraft and operationalreliability. Fortunately for mission planners, it is thought to be
extremely difficult to access potential liquid water volumes
within the vast majority of objects in the outer solar system:a recent analysis of Ganymede, which is the object currently
considered to have the most-accessible water after Europa andEnceladus, suggested that viable Earth organisms deposited on
the surface would have a probability much lower than 1 × 10 −4of reaching subsurface liquid water (Grasset et al., 2013).
For this reason, missions that would not encounter Europa
or Enceladus receive no a priori restrictions on hardware
cleanliness, for planetary protection; rather, these missions
are required to ensure, by careful operation of the spacecraft,that any liquid water bodies discovered during the mission
are not contacted by spacecraft hardware, even after the mission ends. This requirement was applied, in the past, to themissions that discovered potential habitats within Europa andEnceladus: the Galileo spacecraft was de-orbited into Jupiter,
and the Cassini spacecraft was de-orbited into Saturn, in orderto protect the newly discovered watery moons of those planets.
The Juno mission to Jupiter, which will not encounter Europa
during the prime mission, plans to dispose the spacecraft into

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Jupiter—but they also performed calculations to show that,should the deorbit maneuver fail and the inactive Juno spacecraft impact Europa at some point in the future, the impact
energy would be so high as to incinerate all remaining viableorganisms, in a sufficiently high fraction of the total impact
cases in Monte Carlo simulations that the <1 × 10 −4 probability requirement was met (Bernard et al., 2013).
12.5.4.1.2 Cleanliness and Life Detection
The detection of extraterrestrial life is of relevance to planetary protection because extraterrestrial organisms are bydefinition considered biohazards: this is based on long experience from Earth that introduced species can become invasiveor pathogenic. For this reason, outbound-only missions toouter solar system objects that carry life detection investigations do not receive additional cleanliness requirements fromplanetary protection on the basis of instrument capabilities,
beyond the 1 × 10 −4 probability of contaminating liquid waterand potential habitats.
In contrast, additional organic and biological cleanliness
requirements will be imposed on sample return missions frompotentially habitable environments in the outer solar system(currently Enceladus or Europa), to ensure adequate levels ofconfidence in the results of the post-return biohazard test protocol. During the Apollo program, sample collection hardware
was carefully cleaned and samples were (in principle) quarantined until a biohazard test protocol had been completed.
Subsequent to Apollo, a notional “Draft Test Protocol for
Detecting Biohazards” has been established (Rummel et al.,2002), during the course of multiple rounds of studies preparing for missions that would collect samples and return from
Mars. This draft test protocol requires additional refinement(e.g., Kminek et al., 2014), to establish requirements on thelevel of statistical confidence needed to make a determinationthat extraterrestrial samples are “safe for release”—which isa risk assessment that needs to be made at a global societal
level, not solely by space scientists or space agency staff (e.g.,
Haltigin et al., 2018). Confidence that the test protocol is not
generating false-negative results would, of course, be reduced
in proportion to the amount of Earth contamination present incollected samples, and it depends on the capabilities of instruments used to make measurements.
The development of biohazard test protocols and associated contamination requirements is ongoing.

12.5.4.2 MARS MISSIONS
12.5.4.2.1

Planetary Protection Requirements
for Mars: It’s Complicated
The planet Mars has been explored more extensively than any
planet in the solar system other than Earth; likewise, Mars is
also the focus of a wider diversity of human interests. Fromthe earliest discussions of Mars exploration, the potential for
future human colonization/settlement and the possibility ofterraforming Mars were taken seriously, and the potential forbiological contamination from Earth to interfere with theselong-term goals was recognized (e.g., Space Science Board

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Planetary Protection[SSB], 1958). In response to the rapidly increasing scientificinformation about Mars and recognizing the diversity ofshort-term and long-term goals in Mars exploration, planetary protection requirements for Mars have undergone morediscussion and refinement than those for any other target of
exploration.
Spacecraft and hardware not intended to impact Mars areallowed to meet planetary protection requirements by avoiding impact onto Mars. Launched hardware items that were notmaintained in a controlled clean environment—e.g., the upperstages of launch vehicles—are required to avoid impact onto
Mars, for a period of 50 years after launch, at a probabilityof 1 × 10 −4. It is preferred that spacecraft intended to orbit
or flyby Mars should also avoid Mars impact for a period of
50 years, though with a relaxed probabilistic constraint—thisinvolves no greater cleanliness than assembly in controlledenvironments typical for spaceflight hardware assembly. If,
however, impact avoidance is not feasible for orbiter spacecraft, due, for example, to aerobraking, then orbiter missions
may demonstrate that they deliver no more organisms to Mars
than are permitted on landed hardware that is expected tobreak open on impact.
Current planetary protection requirements for the cleanliness of hardware landing on Mars depend both on where
the hardware is intended to land and on the purpose of the
hardware. The Viking program imposed additional cleanliness requirements on some hardware, to ensure the integrityof the life detection experiments by removing contaminationfrom Earth that could interfere with the detection of signals
from Mars. No indications were observed of Earth organisms
being present, so the terminal heat microbial reduction andadditional cleaning of the Life Detection Package did accomplish the goal of eliminating Earth life. However, despite theprogram’s best efforts, signals interpreted as Earth contaminants were the most abundant compounds measured by the
Viking GC-MS instruments. At the time, it was assumed thatthese Earth contaminants were the only compounds present
and that no organics from Mars had been detected (e.g., Space
Science Board [SSB], 1977). Because the Viking landers were
not collecting Mars samples for return to Earth, this interpretation did not put in jeopardy the safety of the Earth, which isof paramount importance to planetary protection.
12.5.4.2.2 “Average” Mars
After the Viking program demonstrated that most of theMartian surface is cold and dry, providing very limited
resources that could support Earth life, cleanliness requirements for Mars landers were relaxed, to eliminate the fourorder-of-magnitude heat-reduction step and protection fromrecontamination implemented on Viking (DeVincenzi et al.,1996). This basic level of cleanliness is required for all Mars
missions, and missions receive a designation of PlanetaryProtection Category IVa if they do not carry life detection
instruments or plan operations to access more-habitable locations on Mars.
Before the terminal full-system heat reduction, the Viking
landers had been cleaned to 300 heat-resistant organisms per

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square meter of spacecraft surface over about 1000 square
meters of area and also carried approximately 200,000 heatresistant organisms in the interior of the spacecraft. The number of heat-susceptible organisms was not measured as part of
the requirement, because any heat treatment that killed resistant organisms would eliminate susceptible organisms at amuch higher rate. These relaxed requirements of less than 300
heat-resistant organisms per square meter, less than 300,000
heat-resistant organisms over all surfaces exposed to the environment of Mars, and less than 500,000 heat-resistant organisms in total (this includes organisms inside hardware that
could break open on impact, such as heat shields, backshells,
and parachutes), are necessary to meet Planetary Protection
Category IVa.
12.5.4.2.3 Special Regions on Mars
Following orbital observations in the 2000s that confirmed
the presence of active gully systems and water ice in thenear-subsurface of Mars, the Viking requirement for four-log
microbial reduction with recontamination prevention wasreinstated for missions targeting locations on Mars whereenvironmental conditions have the potential to provide, atleast transiently, temperatures and available water that could
support growth of Earth life. So-called Mars Special Regionsare, as of 2017, defined as locations where temperatures reachabove −28°C and “water activity” (1/relative humidity) reaches
above 0.5 (equivalent to 50% relative humidity). These regions
include features on Mars where the presence of such conditions is in question (Kminek et al., 2017). Each project planning a landed mission to Mars is required to do an analysisof their proposed landing sites, to establish whether Special
Regions might be present: only if Special Regions are notwithin a landing ellipse that includes 3 standard deviationsof targeting error after parachute opening (3-sigma) would
a project be designated Planetary Protection Category IVa.
Missions that do target areas with potential Special Regions
inside the 3-sigma landing ellipse are designated PlanetaryProtection Category IVc and are required to use microbial reduction processes and recontamination prevention toachieve Viking-equivalent cleanliness of <0.03 viable Earthorganisms per square meter of exposed spacecraft surface.
Missions intended to access Special Regions outside the landing ellipse are required to clean at least the subsystems used
for such access to Viking-equivalent levels and protect themfrom recontamination by other spacecraft hardware.
It is relevant to note that the definition of Special Regions,originally adopted in the mid-2000s, does not follow historicalprecedent in setting conservative limits on parameters of concern to planetary protection, with room for subsequent relaxation: in the 2010s, the temperature limit for Special Regions
had to be reduced from −25°C to −28°C, after additional dataon the capabilities of Earth organisms were obtained.
12.5.4.2.4 Mars Life Detection
The highest concern for planetary protection is to avoid“harmful contamination” of the environment of the Earth,which includes imposing appropriate constraints on future

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round-trip missions, robotic and human. In this context, falsenegative results from in situ experiments to detect Mars life
are of considerable concern, because future requirements
would be set based on an incorrect assessment of potential
risk. One example of the consequences of false-negative
results is that Mars exploration was put on hold for 20 years
because “Viking had shown there were no organics” (Space
Science Board [SSB], 1977)—yet recent data from the SAM
AQ 12 instrument informed a re-evaluation of Viking data, which
identified Martian organic compounds not recognized previously (e.g., Glavin et al., 2013; Freissinet et al., 2015).
Missions to Mars that carry instruments capable of detecting Mars “life forms, precursors, and remnants,” in thelanguage of the COSPAR policy (Kminek et al., 2017) automatically also are capable of detecting biological and organic
contamination from Earth and receive a separate designationof Planetary Protection Category IVb. To address the greater
policy-level concern about Mars life (by definition consideredbiohazardous) being brought to Earth, life detection missions are required, in addition to landing site constraints, toensure that hardware subsystems with a potential to contaminate the life detection experiments meet the equivalent of theViking lander overall requirements: cleaned to 300 resistantorganisms per square meter of surface area, protected fromrecontamination, and reduced by four orders of magnitude.
As noted previously and in histories of the Viking Program,
this level of cleanliness is less than what was required for theViking GC-MS and Life Detection Package, which was set
based on the scientific objectives of those instrument (Daspit
et al., 1988). Currently, rather than setting specific numerical limits on non-viable Earth contamination, planetary protection policy specifies that such requirements be set “driven
by the nature and sensitivity of the particular life detection
experiments” (Kminek et al., 2017), with the expectation thatappropriate limits would be established by the instrument
teams and project management during payload selection andaccommodation, and subsequently monitored for compliance,along with all other planetary protection requirements. This isan effective approach for in situ experiments, but when samples are returned to Earth, additional considerations pertain.
12.5.4.2.5 Mars Sample Return
Mars is of astrobiological interest as a potential habitat for
extraterrestrial life and therefore has the potential to host lifethat is, by definition, considered potentially biohazardous to
the Earth. For this reason, missions planned to collect samples
from Mars and bring them to Earth receive the designation“Planetary Protection Category V Restricted Earth Return,”which means that spacecraft hardware must be cleaned tolevels that will ensure that Earth contamination is not introduced into Mars samples in quantities that could invalidate thebiohazard test protocol that will be performed after return toEarth (e.g., Haltigin, 2018). This is in addition to meeting all
requirements appropriate for mission operations at Mars, aswell as ensuring that documentation of potential contaminationis collected and provided for pre-return Earth Safety analyses
and reviews. During the return phase of the mission, samples

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are required to be contained, so as to ensure a probability ofless than 1 × 10 −6 that a particle greater than 10 nanometersin size is released into the environment of the Earth, including particles adhering to spacecraft surfaces, as discussed in
Haltigin (2018). In the special case of sample return from oneof the moons of Mars, additional calculations would be needed
to assess the amount of material from Mars present in the collected samples, due to recent impact ejection events, such as
the 60-km Mojave impact crater (Chappaz et al., 2013).
After Mars samples have landed on Earth, it is required tocontain them at levels equivalent to the strictest biosafety level(BSL-4/P-4, used for, e.g., ebola virus) and also protect themfrom Earth contamination while early analyses and the biohazard test protocol are performed (Rummel et al., 2002). Thisis required to ensure that the risk to the Earth from retaining
Mars samples is acceptably low. For Restricted Earth Return
missions, “acceptably low” is a regulatory determination thathas not yet been fully developed—currently, there is a containment requirement but not a biohazard test confidence requirement. Containment procedures are required to ensure thatthe risk of releasing extraterrestrial material into the Earth’s
environment is kept under one in a million, which was recommended based on comparison with other risks that humansocieties accept (European Science Foundation [ESF], 2012).

12.5.4.3 HUMAN MISSIONSHuman missions to other planetary targets almost invariably
involve a return trip to Earth—as such, they would receive
requirements equivalent to Planetary Protection Category V.
Current planetary protection policy includes guidelines forhuman missions that focus predominantly on forward contamination. Protection of the Earth must be ensured, but specificpractices to accomplish this have not been established—the
Apollo program provides useful precedent in some areas andcautionary experience in others.
As with robotic missions, planetary protection concerns forhuman missions are divided conceptually by “habitable” vs.
“non-habitable” targets: when humans explore non-habitabletargets, neither contamination of the astronauts or the Earthnor contamination of the target by Earth life is relevant. Marsis the only feasible target for human exploration that is considered as potentially hosting native extraterrestrial life andis potentially “habitable” for Earth microbes; thus, human
missions to Mars have received the most policy-level consideration (e.g., Space Studies Board [SSB], 2002; Conley andRummel, 2010; Kminek et al., 2017; Haltigin et al., 2018).
It is recognized that human missions are unlikely to be
fully contained; thus, provisions must be made to addresscontamination of astronauts by Mars material, as well as
contamination of Mars by Earth microbes. By analogy, withthe requirements for Special Regions, approaches have been
proposed for early human missions that involve allowing agreater level of contamination in areas where humans travel,
while protecting Special Regions to currently required levels.
The degree of separation needed would be based on the technical capabilities of the hardware and human support systems,

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which currently are not well-established. As is routine forplanetary protection, the collection of additional scientificinformation may lead to relaxation of requirements, once it isdemonstrated that the initial level of stringency is not needed.
Two additional factors pertain to the human exploration ofMars, which are not currently covered in planetary protection policy—yet these issues will need to be addressed at apolicy level, before such events occur that require a response
from the global society. The first question is the extent towhich the environment of Mars might be toxic to astronauts
or Earth microbes, in the absence of a Mars biota—this needs
to be understood in order to assess the potential for falsepositive indications of biohazards in samples from Mars.
Measurements made on Mars suggest that the dust contains~1 weight-percent of oxy-chlorine compounds, which are
known to be toxic to humans and some Earth microbes. An
understanding of the potential toxicity of Mars dust may be
important to assess overall risk of human missions to Marsand to provide information both to the astronauts performing
missions and to the societies that pay for them.
The second question, which is explicitly excluded fromplanetary protection policy but still needs to be addressed,
is the extent to which Earth microbes could change during spaceflight, resulting in increased biohazard after they
return to Earth. This issue was raised by the NASA Advisory
Council but has not yet received significant attention, despite
experiments from the International Space Station that seem toindicate increased virulence in Salmonella grown in microgravity (Sarker et al. 2010).
Societal perception and acceptance of these risks will begreatly facilitated by providing accurate and complete information, starting as early as possible in the process of mission
development.

12.5.5

OPEN ISSUES IN INTERNATIONAL
POLICY

12.5.5.1 RELATIONSHIP OF INTERNATIONAL
POLICY TO NATIONAL OBLIGATIONS
The 1967 Outer Space Treaty, by its title, provides for “theExploration and Use of Outer Space,” and planetary protection guidelines, although maintained by the scientific organization COSPAR, also apply more broadly than just scientificexploration. Whether the COSPAR guidelines represent
legally binding “customary law” has not yet been tested incourt, although their recognition in 2017 by UN-COPUOS
as a “long-standing... reference standard... in guiding compliance with article IX of the Outer Space Treaty” could
strengthen that case. All the major international agreementson space exploration have elements that support planetary
protection practices (Achilleas and Crapart, 2003), with thestate responsible for space objects also being responsible
for mitigating “harmful contamination” caused by them. In
addition, the international framework of environmental law,although focused on terrestrial activities, includes languagethat could reasonably be extended to backward contamination

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brought to Earth by sample return missions (Achilleas andCrapart, 2003). In addition, the 1992 Convention on Biological
Diversity, Article 3, states the principle that states have “theresponsibility to ensure that activities within their jurisdiction or control do not cause damage to the environment ofother States or of areas beyond the limits of national jurisdiction.” Whether such areas extend beyond the environmentof the Earth has again not yet been tested in court, but it has
been suggested that a plausible case could be made (Achilleas
and Crapart, 2003).
Supporting these international obligations, some countries
also have national laws that address environmental protection
aspects of space activities. For example, the Russian Federation,
in Decree No. 5663-1, states the principle of “provision ofsafety in space activity, including protection of the environment;” and prohibits actions “to create harmful contamination of outer space which leads to unfavourable changes ofthe environment,” (UNOOSA, retrieved 2018). Although the
US has not yet passed legislation addressing planetary protection, several sections of the Code of Federal Regulations
describe the applicability of the National Environmental
Protection Act to Earth Return missions. In addition, the 1975
Presidential Directive that superseded the Apollo-era NSAM235, PD/NSC-25 on “Scientific or Technological Experimentswith Possible Large-scale Adverse Environmental Effects
and Launch of Nuclear Systems into Space” specifies a consultation process that would need to be followed prior to
implementing a Category V Restricted Earth Return Mission.

12.5.5.2 APPLICATION OF PLANETARY PROTECTIONGUIDELINES TO COMMERCIAL MISSIONS
It is only recently that non-governmental entities havedeveloped capabilities to engage in activities of concern
for planetary protection, and the mechanisms for ensuring“authorization and continuing supervision” (UN, 1967) ofprivate space exploration are still under development. Within
the US, the commercial launch approval process overseen by
the Federal Aviation Administration requires consultation
with the State Department and NASA, and planetary protection compliance for commercial launches has been addressed.
Other countries may have more straightforward internal structures for establishing legal and/or regulatory frameworks forcommercial space exploration.
With the increasing interest and activity in private space
exploration, and considering the potential for global negative
consequences due to the release of a hazardous extraterrestrial
entity, formal processes, both nationally and internationally,
will undoubtedly be needed. Although planetary protection isthe aspect of commercial space exploration with the broadest
potential consequences, the establishment of an appropriate
regulatory framework for commercial space activities is an
issue that extends far beyond planetary protection. For example: if one commercial entity identifies a valuable target andanother entity succeeds in reaching the same target more rapidly, how will rights and responsibilities for use of that target
be determined?

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12.5.5.3 INTERNATIONAL CONCERNS AROUND
RESTRICTED EARTH RETURNOver the past decade, the iMARS Working Group, charteredby the International Mars Exploration Working Group, has
explored requirements for Mars Sample Return and madeconsiderable progress on developing an architecture for handling Mars samples brought to Earth (Haltigin et al., 2018).
The major concern for backward contamination is to prevent
release of extraterrestrial organisms over the entire time forwhich extraterrestrial material is stored on Earth, thus the
precautions taken involve two steps (e.g., Rummel et al, 2002;
Kminek et al., 2014). First, the hardware returning to Earthmust be carefully designed to reduce the risk of accidental
breach to an acceptably low level, until the hardware is placedin a properly designed containment facility. In addition, thesamples brought to Earth must undergo careful testing for possible extraterrestrial life, which is, by definition, consideredbiohazardous. This “Biohazard Test Protocol” must be performed early during the post-return sample analysis period, tominimize the risk of accidental release due to failures in containment. To ensure that the test protocol can detect extraterrestrial biology with high sensitivity, hardware used to collectextraterrestrial samples must be carefully cleaned of Earthcontamination, and information retained about the potential
for contamination to introduced from the earliest mission
AQ 13 phases. This set of requirements was recommended during
the US Apollo program, to minimize the potential for “false
negative” results due to the masking low levels of extraterrestrial biosignatures by higher levels of Earth contamination(e.g., Space Science Board [SSB] 1964).
The most significant long-lasting consequence of space
exploration for human society and the environment of the Earthwould be backward contamination, the release of a novel extraterrestrial entity that has adverse effects—this was recognized
as a potential problem in the 1950s and is explicitly prohibitedby Article IX of the Outer Space Treaty (UN, 1967). It has been
recommended that COSPAR guidelines specify a probabilityof no more than “one in a million” that potentially viable extraterrestrial material be released into the Earth’s environment,a limit that was proposed after a survey of risk/benefit evaluations that are considered acceptable for other human activities (European Science Foundation (ESF), 2012; Haltigin et al.,2018). As mentioned previously, many spacefaring nations
have national laws on environmental protection, as well as theexisting international agreements—but the specific applicability of national and/or international regulatory frameworks to
Restricted Earth Return efforts remains to be elaborated.

12.5.6 SOCIETAL CONSIDERATIONS
12.5.6.1 AMBIGUITY IN A “DETECTION”
OF EXTRATERRESTRIAL LIFE
Planetary exploration is currently done almost entirely byusing taxpayer funding—even companies that have planetary missions in preparation, such as Moon Express, receive

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considerable government funding. Responsible use of thesefunds requires that the benefits of investment in planetary
exploration outweigh the risk of loss, including loss due tolack of investment elsewhere. This is a societal decision, not ascientific or engineering one, so societal perception of exploration activities and scientific conclusions is critical. After
the Viking missions reported a non-detection of Mars life, no
missions were sent to Mars for several decades, despite continued interest on the part of spaceflight engineers and Mars
scientists (Space Science Board [SSB], 1977), because funds
were allocated elsewhere. If it had been recognized at the timethat the Viking mass spectrometers did, in fact, detect Mars
organic compounds, albeit at low levels (Glavin et al., 2013;
Freissinet et al., 2015), the trajectory of Mars exploration
would likely have been quite different.
The need to ensure accuracy in the conclusions of a life/
biohazard detection protocol is of much greater importancewhen the samples being analyzed have been brought backto Earth. There has recently been some confusion regarding
contamination control requirements supporting a Biohazard
Test Protocol, resulting from conflation of concerns associated with “false positive” and “false negative” results (e.g.,
Space Science Board [SSB] 2017). From the standpoint ofinterpreting scientific data, this results from ambiguity about
which “null hypothesis” is being tested (Kminek et al., 2014).
Astrobiologists and scientists interested in detecting extraterrestrial life will err on the side of not announcing a findingof “life” until they have high confidence in the detection:
they are testing the null hypothesis “there is no life in thesesamples.” If Earth contamination is detected but there are notsignals clearly indicative of extraterrestrial biosignatures, thiswould be interpreted as a “non-detection” of extraterrestrial
life. This approach is consistent with careful scientific discovery, and it also ensures that no harm is done to scientists’or space agencies’ reputations, from holding over-enthusiasticpress conferences.

12.5.6.2 THE POTENTIAL FOR UNIDENTIFIED BIOHAZARDS
In contrast, concerns for Earth Safety require avoiding
the release of potential biohazards into the environment of
the Earth, and therefore, they need to test the contrary null
hypothesis: to ensure safety of the Earth if samples are
released, it is necessary to disprove the hypothesis “there is
extraterrestrial life in these samples” (e.g., Kminek et al.,2014; Haltigin et al., 2018). When testing this null hypothesis,
the detection of any Earth contamination would indicate thepresence of biosignatures that could also be associated withextraterrestrial biohazards, and very careful further testing
would be required to evaluate this possibility at acceptablelevels of statistical significance. Samples can certainly beanalyzed in containment, while biohazard testing is ongoing—in fact, many of the measurements made will inform
both scientific and regulatory communities—but the risk thata breach in containment could release a potential biohazard
increases the longer the question remains unanswered. Thisis a societal question, as much as a scientific one: the public

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will be affected, if a breach occurs, so they will also want toknow how safe the samples are. The space agencies bringing extraterrestrial samples to Earth have an obligation andresponsibility to provide accurate answers.

12.5.6.3 QUARANTINE AND SETTLEMENT
The concern about detection of potential biohazards does notstop after the first Mars sample return mission, but the challenge of differentiating Mars life from Earth contamination
will become progressively more difficult. Robotic exploration can be accomplished while maintaining stringent levelsof cleanliness; however, once human missions to Mars are
initiated, the concerns increase in ways that are outside thepurview of planetary protection. All organisms known tobe hazardous to humans are from Earth: this includes overt
pathogens (e.g., Clostridium tetani) and environmental hazards (e.g., Stachybotrys fungi). Despite cleaning protocols,
pathogenic organisms have been identified on the International
Space Station (e.g., Lang et al, 2017), though fortunately, they
have not yet caused illness in astronauts. Societal concerns
could change rapidly, if an astronaut were to become ill froma spaceborne pathogen—as human spaceflight becomes morecommon, policies to control transport of Earth organisms willneed to be developed.
Once humans attempt to settle elsewhere, those environments will facilitate independent evolution, and the possibility of exchanging biohazardous organisms that are originallyfrom Earth will need to be addressed. Current and historicalquarantine procedures may not be adequate, when people,
with their microbes, want to go back and forth. If an infectious disease or hazardous organism has never been present
in an environment, what rules should be imposed to control
introduction? How should they be different for independently
replicating (e.g., most bacteria and archaea) vs. obligate-parasite (e.g., viruses and some eukaryotic parasites) entities?
What about quiescent or zoonotic infections that have no vector, for example, a human with trichinosis or malaria? Should
the rules be different for infections that could spread, given
an appropriate environment, such as Giardia and Clostridium
difficile? All of these issues should be considered, at least at apolicy level, before the actual circumstances develop.

12.5.7SUMMARY AND CONCLUSIONSThis chapter provides a brief summary of planetary protection policy and implementation, including the current context
and historical aspects of its development as well as outlining
applicability to select future missions. The issues that planetary protection addresses range from the highly technical,
including astrobiological and other scientific questions, aswell as engineering implementation, to the purely societal andlegal, including concerns over invasive species and negotiation of international regulations. As with most technical andacademic endeavors, the wider context in which researchers carry out their studies may have an enormous impact on
the research that can be performed. It is important for all

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educated citizens but particularly for researchers involved in
esoteric and expensive taxpayer-funded work, to participate
in the social and cultural conversations that surround them.

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Space Studies Board (SSB). 2002. Safe on Mars Precursor
Measurements Necessary to Support Human Operations on
the Martian Surface. National Academies Press, Washington,
DC. Available at https://www.nap.edu/catalog/10360/safe-onmars-precursor-measurements-necessary-to-support-humanoperations.
United Nations (UN). 1966. United Nations Treaty on Principles
Governing the Activities of States in the Exploration and
Use of Outer Space, including the Moon and Other Celestial
Bodies. Available at http://www.unoosa.org/oosa/en/ourwork/
spacelaw/treaties/outerspacetreaty.html.
United Nations (UN). 2018. Status of International Agreements
Relating to Activities in Outer Space as at 1 January 2018.
Availableat
http://www.unoosa.org/oosa/en/ourwork/
spacelaw/treaties/status/index.html.
United Nations Committee on the Peaceful Uses of Outer Space(UN-COPUOS). 2017. Report of the Committee on thePeaceful Uses of Outer Space, 60th Session. Available at
http://www.unoosa.org/oosa/oosadoc/data/documents/2017/a/
a7220_0.html.
United Nations Office of Outer Space Affairs, translation of RussianFederation Decree Number 5663-1. Available at http://www.
unoosa.org/oosa/en/ourwork/spacelaw/nationalspacelaw/russian_federation/decree_5663-1_E.html.
Wells, H.G. 1898. War of the Worlds. W. Heinemann, London, UK.

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PLANETARY PROTECTION TASK FORCE

http://spacescience.nasa.gov/adv/PPACCharter.htm

NATIONAL AERONAUTICS AND SPACE ADMINISTRATIONCHARTER OF THE
PLANETARY PROTECTION ADVISORY COMMITTEE
OF THENASA ADVISORY COUNCILESTABLISHMENT AND AUTHORITY
The NASA Administrator, having determined that it is in the public interest in connection with theperformance of duties imposed on the Agency by law and with the concurrence of the General
Services Administration, establishes the NASA Planetary Protection Advisory Committee (the"Committee") of the NASA Advisory Council (the "Council"), pursuant to the Federal Advisory
Committee Act, 5 U.S.C. App §§ 1 et seq.
PURPOSE AND DUTIES
1. The Committee will advise the NASA Administrator through the NASA Advisory Council on
Agency programs, policies, plans, and other matters pertinent to the Agency's responsibilities forbiological planetary protection, as defined in NPD 8020.7, including NASA planetary protection
policy documents and components, implementation plans, and organization. The Committee will
provide a forum for advice on interagency coordination and intergovernmental planning related toplanetary protection. The Committee will review and recommend appropriate planetary protection
categorizations for all bodies of the solar system to which spacecraft will be sent. The scope of theCommittee's responsibilities will not include issues that pertain solely to the quality and interpretationof scientific experiments and data.
2. The Committee will draw on the expertise of its members and other sources to provide advice andmake recommendations to the Council. The Committee will hold meetings and make site visits
necessary to meet its responsibilities. The Committee will review reports and recommendations of its
subcommittees, panels, and/or task forces and include them, if adopted, in its reports to the NASA
Advisory Council.
3. The Committee shall function solely as an advisory body and will comply fully with the provisionsof the Federal Advisory Committee Act.
SUBCOMMITTEES, TASK FORCES, AND PANELS
1. Subject to the approval of the Associate Deputy Administrator, the Committee is authorized toestablish subcommittees for particular aspects of planetary protection. Subcommittees will beestablished under Terms of Reference that are approved by the Associate Deputy Administrator.
Subcommittees report their proposed findings and recommendations only to the full Committee for its
consideration. Subcommittee durations will be 2 years, renewable subject to the review of the
Associate Administrator, Office of Space Science, and the NASA Advisory Committee Management
Officer.

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2. Subject to the approval of the Associate Deputy Administrator, the Committee is authorized toestablish temporary task forces for special studies. Task forces of the Committee will be establishedunder Terms of Reference that are approved by the Associate Deputy Administrator. Task forces
provide their reports only to the full Committee for its consideration. Task force durations will be
specified in their Terms of Reference and are renewable only with the approval of the Associate
Deputy Administrator.
3. Members of the Committee may organize themselves into panels of particular areas regarding
planetary protection.
MEMBERSHIP
1. The Committee will consist of 15 to 20 members selected to ensure a balanced representation
among industry, academia, and Government. The Committee members, collectively, should have theskills and capabilities to assess the issues and risks of forward and backward biological contamination
for planetary missions and for biological contamination associated with the launch and return ofspacecraft in interplanetary missions and their potential failure modes. At least four of the Committee
members shall be persons knowledgeable in one or more of the fields of bioethics, law, public
attitudes and the communication of science, the Earth’s environment, or related fields. One member
shall be also a member of the Space Science Advisory Committee, and one shall be a member of theLife and Microgravity Sciences and Applications Advisory Committee.
In addition to the above-designated members, nonvoting representatives shall be solicited from thefollowing US Government agencies:
Department of Agriculture
Department of Energy
Department of Health and Human Services—National Institutes of Health—Centers for Disease Control and Prevention
Department of Interior
Department of Transportation
Environmental Protection Agency
National Science Foundation
Executive Office of the President
Other Government representatives may be solicited in the future with the approval of the Associate
Administrator for Space Science.
The Committee shall also invite the participation of nonvoting liaison representatives from othernational and international organizations undertaking joint solar system exploration missions withNASA.
2. The Chair will be appointed by the Administrator. Members will be appointed by the Associate
Administrator for Space Science with written concurrence of the Associate Deputy Administrator.

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3. The Chair will be a member of the NASA Advisory Council.
4. Chairs of subcommittees and task forces usually will be members of the Committee; members of
the subcommittees and task forces are associate members of the Committee and participate only in thework of the subcommittee or task force to which they have been appointed by the Associate
Administrator for Space Science.
5. Members will be appointed for 3-year terms. At the discretion of the Associate Administrator forSpace Science, members may be reappointed for a second 3-year term.
6. Members will be appointed as Special Government Employees and be subject to standards of
ethical conduct for Special Government Employees of the Executive Branch.

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ADMINISTRATIVE PROVISIONS
1. The Committee will report to the NASA Advisory Council. The NASA Advisory Council will
determine whether or not to formally forward committee recommendations to the NASA
Administrator. The Administrator responds, for NASA, to those recommendations.
2. The Committee will meet two to three times a year. Meetings will be open to the public, except
when the General Counsel and Advisory Committee Management Officer determine that the meetingor a portion of the meeting will be closed to the public in accordance with the Government in theSunshine Act or that the meeting is not covered by the Federal Advisory Committee Act. Meetings of
subcommittees, task forces, and panels will be held as required.
3. The Executive Secretary will be appointed by the Associate Administrator for Space Science andwill serve as the Designated Federal Official.
4. The Office of Space Science will provide staff support for the Committee. The estimated annual
operating cost totals approximately $115,000, including 0.35 workyears for staff support.
5. Members of the Committee will not be compensated for their services but will, upon request, beallowed travel and per diem expenses as authorized by 5 U.S.C. 5701 et seq.
DURATION
The Committee shall terminate 2 years from the date of this charter unless earlier terminated or
renewed by proper authority by appropriate action.

Daniel S. Goldin
Administrator

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Date

1/9/09 4:29 PMPLANETARY PROTECTION SUBCOMMITTEETERMS OF REFERENCE
The Planetary Protection Subcommittee (PPS) is a standing Subcommittee of the NASA
Advisory Council (NAC or the Council) Science Committee, supporting the advisory needs of
the Administrator, the Science Mission Directorate (SMD), and other NASA Mission
Directorates as required. The scope of the Subcommittee includes programs, policies, plans,hazard identification and risk assessment, and other matters pertinent to the Agency's
responsibilities for biological planetary protection. This scope includes consideration of NASAplanetary protection policy documents, implementation plans, and organization. The
Subcommittee will review and recommend appropriate planetary protection categorizations forall bodies of the solar system to which spacecraft will be sent. Outside the scope of the
Subcommittee's responsibilities are issues that pertain solely to the quality and interpretation ofscientific experiments and data.
Per NPD 1150.11, the Subcommittee will be managed under procedures that ensure the same
spirit of openness and public accountability that is embodied by the Federal Advisory Committee
Act (FACA). This includes public meetings as appropriate and public access to Subcommittee
records.
MEMBERSHIP
The membership of the Subcommittee will consist of leading scientists with relevant expertisedrawn from industry, academia, independents and Government institutions. The Administrator,
acting on recommendations of the Council Chairman, the NAC Science Committee, and the
Associate Administrator for SMD, will appoint the Chair and members of the Subcommittee.
Appointments generally will be for a three-year term, with re-appointment and replacement at
the discretion of the Administrator, advised by the Council Chair, the Chair of the NAC Science
Committee, and the Associate Administrator for SMD. A Vice Chair will be selected fromamong the members by the Subcommittee Chair in consultation with the Chair of the NAC
Science Committee.
In addition to regular members, nonvoting representatives from other U.S. Government agencies
with an interest in planetary protection will be invited as Subcommittee observers. Nonvoting
liaison representatives from other national and international organizations undertaking joint solar
system exploration missions with NASA also will be invited as Subcommittee observers.
Invitations to participate as observers in these two categories will be issued by the SMD
Associate Administrator.
MEETINGSThe Subcommittee will meet 2-3 times per year, as necesssary. For joint meetings with otherCouncil Science Subcommittees, meeting agendas will be coordinated with the Chair of the NAC

Science Committee and will be responsive to requests from the Administrator, the SMD
Associate Administrator, and the Chair of the Subcommittee.
REPORTING
The Subcommittee will report to the Council via the Council's Science Committee. Records ofSubcommittee meetings, such as summaries of findings and minutes, will be kept by the
Subcommittee's Executive Secretary and will be posted on the web for public access after
approval by the Subcommittee Chair.
ADMINISTRATIVE PROVISIONSThe Executive Secretary of the Subcommittee will be appointed by the SMD Associate
Administrator. Staff support and travel funds for Subcommittee members for regular meetings
will be provided by SMD although other Mission Directorates may provide support for specificactivities.
DURATION
The Subcommittee will terminate on expiration of the charter of the NAC unless that Charter isrenewed by the Administrator. It may be terminated otherwise at the discretion of the
Administrator. If the Subcommittee terminates, all appointments to it also terminate.

Whistleblower Comments on Agency Responses to Supplemental Questions
OSC File No. DI-21-000239
15 July 2023
SummaryNASA's responses to OSC's supplemental questions, submitted after NASA's initialinvestigation failed adequately to address my whistleblowing concerns, continue toconfirm the basis for my initial filing: Starting with the Mars2020 mission, NASA's programof Mars Sample Return is putting the Earth at risk of contamination by extraterrestrial
biohazards, because the program will be unable to detect Mars biosignatures in samples
brought to Earth from Mars due to excessive contamination by Earth biology.
NASA justifies waiving planetary protection requirements for low levels of Earthcontamination by claiming the probability of Mars biohazards should be low, ignoring
decades of international scientific consensus that emphasize the risk is not zero. These
decisions violate NASA policies on planetary protection, US regulations including the
National Environmental Protection Act and PD/NSC-25 on Experiments with Possible
Large-scale Adverse Environmental Effects, and Article IX of the Outer Space Treaty.
Some possible negative consequences of a Mars biohazard release are illustrated by the
recent global COVID pandemic: massive societal upheaval and many trillions of dollars ineconomic damage.
Further, actions taken by NASA and the Mars Exploration community after my initial filinghave introduced conflicts of interest into the management of planetary protection, both atNASA and also within the larger US government, potentially leading to lax oversight ofcommercial space exploration and collaboration with international partners.
If consistent and appropriate regulatory oversight of planetary protection is not
implemented before Mars materials are brought to Earth -- by either public or private
missions -- undetected martian biohazards could be released into the environment of the
Earth and cause potentially-global negative consequences.
The amount of Earth biological contamination known to be present on Mars2020 hardware
collecting samples at Mars means biosignatures will certainly be detected in samples, if the
hardware is returned to Earth. The safety of Earth should not rely on assuming that noMars biohazards are present, just because Earth contaminants were found.

pg. 1 of 9

Narrative Response
Cover Letter
The undated letter signed by Casey L. Swails, that accompanies NASA's supplemental
report on OSC questions transmitted in March 2023, attempts to explain why NASA's
failure to implement planetary protection on Mars2020 in accordance with NASA's own
policies is not "a violation of law, rule, or regulation; gross mismanagement; an abuse of
authority; or a substantial and specific threat to public health."
This cover letter states that NASA planetary protection policies "allow for processes towaive or modify requirements by responsible officials when appropriate", and then goes on tostate that the NASA Planetary Protection Officer (PPO), the Associate Administrator for the
Science Mission Directorate (MDAA), and the Chief of the Office of Safety and Mission
Assurance (SMA), via their approvals of waivers, all:"were aware that regolith (as opposed to rock) samples would exceed certain baseline
parameters but concluded that the risks were acceptable in light of various mitigations."
The two documents cited as relevant in the cover letter, NASA Procedural Requirements(NPR) document 8020.12D and Interim Directive (NID) 8020.109A on 'PlanetaryProtection Provisions for Robotic Extraterrestrial Missions", both use identical wording in
the requirement for making decisions about Mars sample contamination:"5.3.3.11 An independent science and technical advisory committee shall be constituted withoversight responsibilities for materials returned by a Mars sample return mission."
Multiple scientific committees going back to 2014 deliberated extensively to establish
baseline contamination requirements for Mars2020 sample return hardware. The NASA
officials who approved the waiver, two of whom were neither planetary scientists nor
experts on planetary protection, hardly qualify as 'an independent advisory committee'.
The cover letter cites NID 8020.109A, which expired in 2019, as if it supersedes NPR
8020.12D, which is the document applicable to the Mars2020 mission -- but it neglects tocite NPR 8715.24, which is the current NASA policy. All three documents include
requirements to presume that "returned samples contain hazardous biological material"
until test results support a different conclusion. NPR 8715.24 imposes the following
requirement on the same three NASA officials mentioned in the cover letter as deciding towaive the baseline contamination requirements on Mars2020:"3.4.3 The MDAA, in coordination with the Chief, SMA and the PPO, shall negotiate a process
to assure the safety and containment of Earth-return samples, governed under PD/NSC-25,
Scientific or Technological Experiments with Possible Large-Scale Adverse Environmental
Effects and Launch of Nuclear Systems into Space, in consultation with OIIR, relevant U.S.
government agencies, and international partners. "pg. 2 of 9

The wording of Presidential Directive/National Security Council-25 (PD/NSC-25), which
subsumed regulations imposed on the Apollo Program Lunar Sample Return, is quite
specific: the Directive covers experiments reasonably subject to "allegations that they might
have major and protracted effects on the physical or biological environment", which "are to
be included under this policy even though the sponsoring agency feels confident that suchallegations would in fact prove to be unfounded."
Procedures specified in PD/NSC-25 include working with the Directors of the Office of
Science and Technology Policy and what is now the Environmental Protection Agency(provision 1); consulting with the Secretary of State, National Academy of Sciences, and"international scientific bodies or intergovernmental organizations" when experiments
could have "adverse effects beyond the US" (provision 6); and obtaining approval from the
President when an experiment "may involve particularly serious or protracted adverse
effects" (provision 7). Provision 8 mandates "early and widespread dissemination of public
information explaining the purpose, benefits, and assessments of impacts."
Waiving baseline contamination requirements on hardware designed to collect presumedto-be-hazardous Mars samples should qualify for the "protracted adverse effects" categoryof PD/NSC-25 -- particularly when the accepted baseline requirements were subject toconsiderable dispute over concerns around potential lack of stringency and masking ofMars biosignatures (e.g., the 2014 Organic Contamination Panel Dissenting Report).
Despite naming the same three officials, the letter provides no evidence that the provisions
in NPR 8715.24 or PD/NSC-25 were followed -- instead, it notes that safety assessment
protocols have not yet been established, which is in direct contravention of decades ofscientific advice based on lessons learned from the Apollo Back Contamination Committee.
The letter also includes a bizarre aside about hexane being effective for some uses but notothers, and reiterates a comment from the previous NASA response to the effect thatMars2020 achieved similar levels of bioburden control as previous Mars missions.
This last apparent non-sequitur is actually quite supportive of my initial filing, because
every Mars mission to date that was equipped with appropriate instruments has detected
Earth contamination carried along on the spacecraft. My comments of 7 October 2022 cite
scientific evidence from the Viking and Mars Science Laboratory missions that demonstrate
results initially interpreted as indicating only Earth contamination in samples analyzed by
Viking actually masked the presence of organic compounds from Mars. Levels of biologicalcleanliness achieved on even the cleanest previous mission left contamination that
already interfered with the sensitive detection of possible Mars biosignatures.
As PPO, since 2009 I advocated for the applicability of PD/NSC-25 to Mars Sample Return:its' inclusion in NPR 8715.24, although that document took effect after the launch of theMars2020 mission, serves to confirm the relevance. In light of NASA requirements and US
presidential directives, this cover letter provides evidence confirming all of the violations it
mentions, except the 'specific' qualifier to the public health threat, have occurred.

pg. 3 of 9

Developments since 2021
NASA's acknowledgement of PD/NSC-25 as applicable to Mars Sample Return is a positive
step, but a number of other developments have taken place since my removal as PPO andwhistleblowing activities that are both problematic and relevant to my original filing.
i) The first has to do with the structure of NASA's Safety and Mission Assurance (SMA)
reorganization and the placement of planetary protection within it. As PPO, my position
was located at NASA Headquarters and reported to the Associate Administrator of the
Science Mission Directorate. The new SMA structure has the Planetary Protection Officer
located at the Jet Propulsion Laboratory (JPL), where the Mars Program is managed,
reporting through several layers of local management before reaching NASA Headquarters.
JPL is notorious for an organizational culture in which flight projects take precedence over'line' organizations; this structure has regularly been cited for lack of transparency leading
to project delays or failures. In 2022, the Independent Review Board investigating delays
on the Psyche mission (1) found that "A culture of “prove there is a problem” led toimportant issues raised by team members being disregarded" and " JPL institutional issues
are serious and require urgent action."
When people tasked with exerting regulatory oversight are co-located within a culture
where their colleagues actively resist elevating potential problems, the pressure to relax
oversight becomes intense. For planetary protection on Mars Sample Return, inadequate
oversight could put the environment of the Earth at risk.
ii) The second recent development involves how NASA/JPL are compartmentalizing the
National Environmental Protection Act (NEPA) environmental impact process for Mars
Sample Return, by segregating the Mars2020 mission from the rest of the Sample Returncampaign.
The Preliminary Environmental Impact Statement for Mars Sample Return (PEIS, 2) claims
that all environmental impact assessments related to Mars2020 were addressed during theMars2020 NEPA process.
However, the Mars2020 Final Environmental Impact Statement (FEIS, 3) addresses only
the launch of the Mars2020 mission, and provides no information about levels of Earthcontaminants present in sampling hardware, nor does it mention how (in)action by the
Mars2020 project could affect Earth Safety after sampling hardware return. The FEIS
response to public feedback suggesting "leave Mars long-distance" is: "Actions not related to
the Mars 2020 mission are beyond the scope of the EIS."
The Mars Sample Return PEIS continues the compartmentalization of Mars2020 from therest of Sample Return, by arguing for a low probability of viable Mars organisms being
harmful or present in samples brought to Earth. It then implies this somehow relieves theneed for high-sensitivity sample analysis within containment:
pg. 4 of 9

"Because it is currently thought the potential for pathogenic effects from the release ofsmall amounts of Mars samples is regarded as being very low, the analysis of Health and
Safety in Section 3.4 focuses on the design mitigations and protocols utilized to minimize
the potential risk associated with Mars sample release during landing and recovery." (2, pg
3-4; paraphrased on pg. 3-9).
The a priori position that hypothetically low biohazard reduces concern is an explicit
violation of requirements in NPR 8715.24 and section 5.3.3.1 of NPR 8020.12D and NID
8020.109A, which requires that "Samples returned from Mars by spacecraft shall becontained and treated as though potentially hazardous until demonstrated otherwise."
The Mars Sample Return PEIS discusses the required biohazard test protocol in threeparagraphs of a 342 pg. document, and allocates responsibility for developing it to "A
multidisciplinary team of scientists and experts (e.g., engineers, occupational safety andhealth professionals, BSL-4 facility managers, etc.)". Information about the level of Earthcontamination introduced into samples to be returned is an essential input forunderstanding how sensitive a test protocol could possibly be, since contamination levels
determine measurement background and baseline detection sensitivity -- but how the
proposed future team is intended to obtain such information is left undisclosed.
The PEIS does specify that this team is to rely on findings of the Sample Safety Assessment
Protocol (SSAP) working group of the Committee on Space Research (COSPAR), which may
sound impressive to an uninformed reader. In reality, NPR 8715.24 requires only:"reasonable efforts to implement planetary protection measures generally consistent with
the COSPAR Planetary Protection Policy and Guidelines or the planetary protection
measures NASA would take for like missions."
As noted in presentations associated with the PEIS rollout, the only NASA missions
analogous to Mars Sample Return occurred during the Apollo Program: containment
failures during the Apollo Lunar Sample Receiving process were widespread and are welldocumented (see 4 for recent media attention).
iii) The third recent development is perhaps the most concerning, as it involves asystematic subversion of the US scientific advisory process that should ensure government
actions around planetary protection are transparent under the Federal Advisory
Committees Act (FACA), and based on a solid and unbiased scientific foundation.
In 2015, as PPO and following recommendations from the Planetary Protection
Subcommittee (PPS) of the FACA-chartered NASA Advisory Council, I categorized theMars2020 mission as the initial element of a Mars Sample Return campaign, on the basisthat hardware carried on the Mars2020 mission is intended for return to Earth so any
future biohazard detection protocol would require information about Earth contamination
introduced during sample collection by Mars2020. This perspective met with strong
opposition from NASA management, and the PPS was allowed to meet only twice more.
pg. 5 of 9

Starting in 2018, the NASA Advisory Council convened several short-lived committees that
included planetary protection among other commercial and technological subjects, but asof July 2023 there appears to be no committee within the NASA Advisory Council
designated as having responsibility for providing independent external advice on planetary
protection. The Planetary Science Advisory Committee website includes the explicit caveatthat "Responsibility for biological planetary protection is outside the purview of the PAC."
In parallel, the Space Studies Board of the US National Academies of Sciences, Engineering,and Medicine (NASEM) started taking on more 'advisory' responsibilities for planetary
protection, and in 2020 NASEM convened a 'Committee on Planetary Protection' (CoPP),
sponsored by NASA, that has engaged in a meeting schedule much more frequent thanpermitted by the budget of the NAC/PPS. Between September 2020 and July 2023, the
CoPP met 35 times, of which 15 meetings were fully closed, 19 meetings were partiallyclosed, and only one meeting, a 'Public Briefing' on 7 October 2021, was entirely open.
The membership of the NASEM CoPP is heavily skewed towards commercial and nonacademic professionals: of the 13 members listed in July 2023, three are 'independent
consultants' who specialize in commercialization of space, two are current or former space
agency employees, and one is employed by a company specializing in space exploration.
This contrasts with the Committee on Astrobiology and Planetary Sciences, on which only
two of the 19 members hold positions with duties not focused on basic scientific research.
Only two members of CoPP have any expertise in biology, despite the primary goal ofplanetary protection being to prevent contamination by biohazards.
The new co-chair of the CoPP, installed in March 2023, is Dr. Lennard Fisk, whose
revisionist history and negative perception of planetary protection when serving as
President of COSPAR was strongly disputed in print by the first and longest-serving Chairof the COSPAR Panel on Planetary Protection (5). The COSPAR SSAP working group is
identified in the Mars Sample Return EIS as the source of advice on implementing abiohazard detection protocol, yet meetings of international organizations are not subject to
FACA -- and meetings of the COSPAR Panel on Planetary Protection, historically open to all
COSPAR colloquia attendees, under Dr. Fisk's presidential tenure were increasingly closed.
The National Academies are also not formally subject to FACA, and the limited material
made available as having been discussed by the CoPP includes a significant fraction that
advocates for further relaxation of planetary protection requirements specifically tofacilitate commercial space exploration. Given this, the level of closed discussion andapparent conflicts-of-interest among committee members of the CoPP is unusually high.
The potential consequences of a decision to relax planetary protection requirements oncommercial Mars missions are no different than for Agency missions. PD/NSC-25
mandates public communication only after a decision is made, but both NEPA and FACA
require more widespread public consultation and transparency than is evident to date.
How will regulatory compliance be assured, if the US government starts making decisions
based on advice from predominantly closed international and NASEM meetings?
pg. 6 of 9

Detailed Responses to Follow-up Questions
Question 1: As with the original NASA report, this response carefully selects only a subset
of disclosures to address, and the information being left out is as important as the parts of
the questions for which responses are given. The response to Question 1 makes no effort
to justify the 'system deviation' other than to say it was approved by several bureaucrats.
It then proceeds to describe some "mitigations" proposed as effective for removing surface
contamination from the drill bit -- but which certainly would not have any effect on
contamination covering other surfaces, such as the interior of the sample collection tubes
where contamination is easily transferred to Mars samples.
Further, the approach of using "vibration to further clean the inside of the regolith bit" could
be counterproductive, in that questions have been raised about the potential forcontaminants to be abraded or leached out of the material from which the hardware is
made: my source is verbal communication from a Mars scientist who requested to remain
anonymous due to fear of retaliation. Concerns about leaching-, abrasion-, or vibrationinduced contamination are entirely omitted from the NASA response.
Question 2 requests directly an explanation for the claim, repeated both in the first report
and the last lines of this response to question 1, that "failure to meet baseline TOC does notpresent a significant threat to planetary protection but rather potentially affects some Mars
sample return science."
NASA's response is missing not only information, but also any process of logical inference.
Starting at the end, the last several lines of the response -- which may be a quote orparaphrase from the COSPAR Sample Safety Assessment Framework? -- state:" The sample safety assessment purpose is to exclude biological origin. Total organic carbon
exceeding requirements may potentially hinder pace of the process by requiring additional
investigation of organic-rich regions slowing the overall sample safety assessment "Since the need "to exclude biological origin" is the primary focus of planetary protection -being absolutely essential for assuring Earth Safety from extraterrestrial biohazards -- toallow higher-than-baseline TOC to "hinder pace of the process" can't be anything other thana threat to planetary protection: every day in containment is another chance forcontainment to fail.
A substantial fraction of the Question 2 response is dedicated to explaining the different
categories of contamination being considered, to make the point that the organic
compounds created by biological organisms represent only a limited subset of allcompounds it is possible to make using organic chemistry. However, the 'tier 1'
compounds are proposed to be biology-related based on Earth biology, which may be quite
different than organisms from Mars.

pg. 7 of 9

The reiteration that a safety assessment protocol has not yet been established also begs thequestion of how the approach for dividing Earth contaminants into different tiers ofcompounds was validated, and why it was considered to be adequately informative for
evaluating the presence of potential Mars biohazards?
The cited 'Sample Safety Assessment Framework' should focus primarily on the sensitivityof measurements to detect the presence of a potentially-very-small number of viable Mars
organisms -- because viable organisms are predicted to be the most damaging potential
biohazards -- and only secondarily attempt to distinguish between small-moleculecompounds that could be made via biological or non-biological processes.
Instead, the response to this question appears entirely oblivious to the certainty that higher
levels of Earth (biological) contamination will make detection of "biomarker compounds"
more inevitable -- yet at the same time will open even wider the question of whether any ofthe detected biomarkers are actually from Mars.
As detailed in my previous response, on Mars in the 1970s the Viking project failed toanswer this question correctly -- it wasn't until 2015 that the Mars Science Laboratory
confirmed the Viking-era detection of Mars organics, that previously had been discounted
as Earth contamination.
Knowing which planet a biomarker comes from is absolutely "significant" for planetary
protection to assure Earth safety -- and presumably also for Mars science, since we alreadyknow there's life on Earth. Evidently, the NASA/JPL Mars Program hasn't learned this,despite five decades and many billions of taxpayer dollars invested in Mars exploration.
Question 3 addresses the hexane wash, and received a response so tautological that there's
not much inference to pick apart. No matter how often NASA declares that what Mars2020
did was 'approved' or 'accepted' by some bureaucrat or NASA-sponsored committee, thisrepetition does not address the actual potential for Earth contamination to interfere with
detecting Mars organic compounds that could indicate potential Mars biohazards.
If the US and EU taxpayers who are funding Mars Sample Return truly understood the risks,
would they really consider it worthwhile to spend additional billions of dollars/Euros torepeat the 50-year-old mistakes made by Viking -- not to mention possibly putting theenvironment of the Earth at risk from undetected Mars organisms in samples broughthere?

pg. 8 of 9

References(1) Report and NASA Response to Psyche Independent Review Board Investigation:
https://go.nasa.gov/3UtmbOz(2) NASA Preliminary Environmental Impact Statement:
https://www.regulations.gov/document/NASA-2022-0002-0175(3) Mars2020 Federal Register Announcement of Final EIS, links to documents on page:https://www.federalregister.gov/documents/2020/01/24/2020-01179/nationalenvironmental-policy-act-mars-2020-mission(4) Scoles, S. "Cosmic Luck: NASA’s Apollo 11 Moon Quarantine Broke Down" The New
York Times, 9 June, 2023:
https://www.nytimes.com/2023/06/09/science/nasa-moon-quarantine.html(5) Rummel, J.D., 2023. Space Research Today, No. 216, COSPAR, pp. 58-61.

pg. 9 of 9