**Laboratory for Atmospheric and Space Physics**

Duane Physics Building

UCB 392

Boulder, CO 80309-0392

Telephone: (303) 492-8004

Facsimile: (303) 492-6946

Internet: bruce.jakosky@lasp.colorado.edu

13 July 2004

Dr. James Garvin, Lead Scientist for the Moon and Mars

NASA Headquarters

Washington, DC 20546

Dear Jim,

On behalf of its executive committee, I am reporting to you on the
meeting of the Mars Exploration Program Analysis Group (MEPAG) that was
held near JPL on 30 June - 2 July, 2004. Despite the schedule conflicts
and proximity to a national holiday, we estimate that more than 150
people participated in the meeting. As anticipated, we had substantial
"drop in" attendance from members of the MER science and operations
team, from members of the Cassini science team who were at JPL for the
Saturn Orbit Insertion on the 30th, and from international partners,
some of whom were at JPL for Cassini-related activities.

The major objectives of this MEPAG meeting were:

-   Develop a common understanding of the current status of the Mars
    exploration (on an international basis), its relationship to other
    NASA programs, and NASA's current needs for program analysis by the
    community.

-   Discuss the second edition of the MEPAG "Goals and Objectives"
    document and whether there is a need for revisions.

-   Discuss status and results from ongoing/previous MEPAG analysis
    teams, and launch a new set of analysis teams on key issues for the
    program.

-   Give the community a forum for raising questions, issues, concerns,
    and compliments.

(Note that, although the MSL mission was of intense interest at this
meeting, it was not a topic of discussion at this meeting due to the
imminent deadline on the open AO soliciting instruments. Participants
were very careful to respect the need to not discuss MSL and, in fact,
there was no discussion of MSL beyond publicly available information.)

**The NASA 2011 missions**

Based on the presentations that we have seen, there has been
considerable ambiguity so far in defining the 2011 missions, which at
this time appear to include two Scout missions and a separate
human-precursor testbed mission. Concerns were expressed over the
as-yet-uncertain nature of the latter, over the ability to successfully
design, build, and launch three separate spacecraft for a single launch
opportunity, and over whether adequate funding would be available to
support three missions without inappropriately squeezing each mission to
the detriment of their science. MEPAG would appreciate receiving
clarification on these points.

Additional concerns were raised over the uncertain nature of the testbed
mission. At the request of NASA HQ, MEPAG has convened a two-pronged
Human Precursor Mission Science Steering Group in order to provide
science input in this area. The two foci of the SSG involve both the
measurements that would be made by such a mission and the identification
of technology and infrastructure that, together, would reduce risk and
cost in a later human mission. This SSG is just in the process of
forming, and we don't expect results to be available until later in this
calendar year.

A different issue that was raised with regard to the 2011 Scouts
involves, in essence, the "ground rules" behind such missions. The Mars
Scout Program was originally conceived at least in part as an
opportunity for the community to identify and address high-priority
science areas that were not a part of the core science program as it is
currently being implemented. Examples of such science areas might
include obtaining an understanding of the major components of the
circulation of the atmosphere, deploying a network of geophysical
stations to explore the martian interior, or examining the nature of the
upper atmosphere and its interactions with the sun and the solar wind.
This concept is widely viewed in the science community as the most
appropriate ways for the Scout program to operate. This would be in
contrast, for example, to a program in which goals were identified ahead
of time and proposals solicited that would be aimed at those specific
missions (as with the New Frontiers program, for instance), or in which
missions that were aligned scientifically with the goals of the core
program might be given preference in selection. We encourage NASA HQ to
ensure that the Scout program be operated with the visibility and
clarity that we have come to expect, and to let individuals in the
community compete openly in the marketplace of ideas (via formation of
science teams under the direction of an individual Principal
Investigator). We note that the issue of Scout goals could be
complicated by the existence of the Exploration Initiative and by the
role it might or might not play in the Scout missions.

**The NASA 2013 mission**

There was some ambiguity in the presentations made by the program
offices as to whether a decision had already been made to fly a Mars
sample return (MSR) mission in 2013. The relative scientific merits of
an MSR, followed by sample analysis back here on Earth, compared to the
*in situ* investigation by, for example, an Astrobiology Field
Laboratory (AFL) have not been addressed in light of recent discoveries
from the Mars Exploration Rovers and Mars Express and the current state
of technological readiness. As such, a decision on which mission to fly
in 2013 is premature from MEPAG's science perspective. The first-order
science definition of an AFL has just been completed (by a MEPAG science
steering group), and an MSR SSG is being convened in order to address
the science issues. The MSR SSG is just now being formed, and we are in
the process of developing the charter for it. We anticipate that the
input from these groups, in particular taken into account by the
upcoming Mars Science Program Synthesis Group (MSPSG II), will play a
central role in defining what the 2013 mission will be. We note,
however, that it is imperative that, even without a decision today as to
which mission will fly, adequate advance planning and technology
development be carried out in both areas in order to allow a real choice
to be made at a future date.

If an MSR is to fly in 2013, there is a concern that the mission would
be designed in order to satisfy the legitimate needs of the human
exploration preparation rather than to maximize the science return.
These two different objectives are likely to have very different
requirements in terms of the nature of a sample (rocks versus dust/soil,
for example) or the location from which it is obtained (geologically
challenging versus human safety), for example. We urge that science play
the central role in designing and implementing MSR.

**Exploration program**

Although there is sometimes a perceived antagonism between the robotic
science program and the human exploration program, this was not in
evidence at our meeting. The MEPAG was fully engaged by the totality of
the President's vision. However, as scientists, we want to ensure that
the fully developed exploration program involves an appropriate level of
science. It is imperative that NASA HQ work diligently to ensure that
the Mars program remains a broad program that pays due attention to the
science goals of the program, and that the input of the science
community be given due consideration in programmatic decisions. Human
exploration without science is correctly derided as "tourism" or as only
"flags and footprints". The Apollo Program demonstrated the great
benefits that accrue to both exploration and science when the program is
run cooperatively.

**Lessons learned from MER**

A major topic of discussion involved trying to capture the lessons
learned from the programmatics, operations, and science of the MER
missions. While not science *per se*, these issues have a tremendous
impact on our ability to do science, and we wanted to capture these
issues now so that they could affect planning for future Mars surface
missions in particular. Some of the most significant issues that were
raised were:

\- The MER mission demonstrated unequivocally the importance and value
of mobility in carrying out science operations on the martian surface.
Without rover mobility, for example, the Opportunity spacecraft would
have sat tantalizingly close to "Opportunity Ledge", unable to
investigate it close up and in detail and thereby make the discoveries
that it has. In the words of one key Mars scientist and member of the
MER team, trying to carry out this type of science mission without
mobility "is just plain stupid". \[Other types of missions require
different types of mobility. For example, the Phoenix mission obtains
vertical mobility via digging in order to access subsurface ice.\]

\- The ability to relay data back to earth through a communications
relay via an orbiter, rather than relying solely on direct-to-earth
communications, was fundamental to the success of the MER mission. The
vast majority of the MER data was relayed back to Earth either through
MGS or Odyssey, and, without such a relay, surface operations and
scientific results likely would have been much more limited and
operations planning would have been slower.

\- There was tremendous scientific value in having two rovers instead of
just one. With a goal of determining whether water had been present (and
geologically significant) on the surface, and with two sites chosen for
very different reasons and based on very different characteristics, it
was not obvious that either would give definitive results. In fact, one
did very readily, and the other is just now beginning to divulge its
water-related secrets, and only grudgingly. Again in the words of a key
Mars scientists, "Given the uncertainties of interpreting orbital data
with limited ground truth, we should strive to always have more than one
landed vehicle at each landing opportunity."

\- MER has demonstrated in a compelling way the ability of a robotic
spacecraft to carry out quantitative field geological investigations, a
conclusion that was widely questioned prior to the mission.

\- There is tremendous science value in selecting participating
scientists (PSs) for a mission early enough that they can become fully
integrated into the science team. Ideally, selection should be as much
as a year prior to arrival or landing, so that the PSs can participate
in the training for the mission, in the development of data reduction
and analysis algorithms, and in the planning for the mission. Such was
the case for MER, and it contributed substantially to the success of the
mission. Other missions have had (or are planning) PSs added at orbit
insertion or landing, and this severely impacts their ability to
participate fully in the mission.

\- Funding and planning for mission operations should reflect the
likelihood of a longer-than-nominal mission duration. Experience shows
that once a spacecraft gets past its initial EDL and check-out period, a
long mission is very likely, and planning should allow for this. We
recognize the inherent problem with a long planned lifetime increasing
the estimated total mission runout costs, but these costs will be there
whether we plan for them or not. In the case of MER, we also note that
there appears to be broad consensus that money used for an extended
mission is being incredibly well spent.

\- A significant factor in the success of the MER missions was the
effective way in which the science and engineering teams were melded
into a single flight team, in contrast to the alternative in which
distrust of each group by the other negatively impacts their ability to
work together. MER demonstrated the high value of having the science and
engineering teams working together rather than being antagonistic.

There were other lessons learned involving, for example, autonomy for
target approach and instrument placement, the important role that
students and post-docs played in mission operations and data analysis,
the importance of adequate training prior to landing, landing precision,
the importance of obtaining definitive non-Fe mineralogy, and vertical
mobility (on MER, via trenching and ratting). We would be pleased to
elaborate on these issues at an appropriate time.

**Update of the MEPAG Goals and Objectives Document**

Another major topic of the meeting was to discuss recent scientific
discoveries and results, primarily from the Mars Exploration Rover and
the European Space Agency Mars Express missions, and whether we need to
update the MEPAG-sponsored Mars Science Goals and Objectives (G & O)
document in light of them. As you know, the original 2001 G & O document
has played a significant role in helping to determine the scientific
directions of the Mars program, both at the mission level and at the
future pathway level. MEPAG recently completed a year-long process of
revising that document in order to bring it up to date and to improve
the degree of scientific balance from the original 2001 version. The
issue on the table at this meeting was whether we needed to make major
changes in the 2004 document in the light of the new discoveries, or
make only minor changes or perhaps no changes at all. Minor changes
could be accommodated with a small amount of editing, while major
changes would require further involvement of the community in order to
maintain the "consensus" nature of the document.

In order to address this issue, we heard detailed science presentations
from the MER and MEX science teams, and opened up the discussion to
allow attendees to raise scientific results and issues that were not
necessarily connected to these missions. The Goals and Objectives
standing MEPAG committee (led at this meeting by Glenn MacPherson in the
place of committee chair Jeff Taylor, who had a schedule conflict) met
in the evening to discuss the results and to consider changes. They
reported back to the MEPAG as a whole, and the attendees engaged in a
spirited discussion of the significance of the results for the Goals and
Objectives. The G & O committee recommended a small number of minor
modifications to the report, and these were discussed and vetted by the
attendees. Final changes will be transmitted to Glenn and to Jeff, and
through them to the MEPAG Executive Committee. We anticipate that the
Executive Committee will make any necessary final modifications prior to
accepting the report, and that it will then be ready for formal
publication in print. In light of the imminent deadline for proposal
submissions for the Mars Science Laboratory and the important role
played in proposal evaluation by the G & O document, we will not approve
or publish any changes until after the proposal deadline. Further
revisions will be considered following future major discoveries and/or
new results.

**Pathways and program flexibility**

The scientists who attended the MEPAG meeting were very pleased with the
opportunity to discuss the recent science results from MER, MEX, and
elsewhere, and to consider their ramifications for planning the future
of the Mars program. The flexibility that was intended to be built into
the program, to allow the program to be responsive to discoveries, is
both present and highly valued.

Part of this flexibility requires that we not "stovepipe" the program so
that all future missions will automatically visit the very interesting
region in which Opportunity landed. We will obtain fundamentally new
types of data from the Mars Reconnaissance Orbiter and when the MEX data
are fully integrated and synthesized, and we anticipate that these data
will allow us to compare the Opportunity site with other locations and
to determine whether possibly more interesting or exciting sites exist.
In addition, scientific questions were raised about whether the geology
and geochemistry at the Meridiani landing site would be conducive to the
long-term preservation of the organic molecules that will be the major
emphasis of the MSL mission and beyond. It is imperative that the
landing sites for the future missions be kept open today, and that a
well-defined and structured process be implemented in order to allow
open debate and discussion of the scientific value of possible landing
sites, in order to take advantage of the new data and to maintain the
program flexibility to respond to ongoing discoveries.

**Science Steering Group reports**

MEPAG heard reports on three SSGs, two of which have completed and
submitted their reports and one of which is in process. The two
completed reports addressed issues of organic contamination of samples
delivered to instruments for the MSL mission (and, by analogy, other
future missions) and the scientific direction of the Astrobiology Field
Laboratory. The reports from these groups have been provided to the
appropriate project offices at JPL, where they are being integrated into
mission planning. The ongoing SSG addresses scientific linkages between
the Moon and Mars, and is specifically in response to the announcement
of the vision for NASA by the President; this SSG presented its
preliminary report, and anticipates completing the report in the near
future. MEPAG was singularly impressed with the quality and depth of the
analysis carried out by each of the SSGs, the more so in that many of
the questions addressed by them were originally ill-posed or
ill-defined. I would be pleased to discuss the specific recommendations
of the SSGs with you. One important conclusion that we would like to
highlight is that these SSGs are an outstanding way to involve the
science community in providing scientific input that feeds into the
programmatic decisions that are to be made; there is no effective
substitute or alternative.

**Summary observations**

Finally, let me comment on the overall perspective by MEPAG of the Mars
program. The community consensus is that we are in a tremendously
exciting time in exploring Mars. The MER mission has achieved some
spectacular results. The remote sensing by the MEX, MGS, and Odyssey
spacecraft is continuing to shed new light on science questions and to
raise new questions. The upcoming slate of missions that are in advanced
states of planning and implementation\--MRO, Phoenix, and MSL\--and the
missions to follow that are in earlier planning are exciting science
missions that address significant questions. And the renewed emphasis on
the combination of exploration and science, and of human and robotic
missions, is creating new opportunities and a sense of real advance.
NASA is making great leaps forward, and we all are anticipating exciting
and fundamental science to come from this program.

Please do not hesitate to contact me or any of the members of the MEPAG
Executive Committee if we can provide additional details or elaborate on
any of the issues discussed here.

Sincerely,

![](media/image1.jpeg){width="2.178472222222222in"
height="0.9708333333333333in"}

Bruce M. Jakosky

Chair, MEPAG

cc: Orlando Figueroa, NASA HQ

Firouz Naderi, JPL

Noel Hinners, Univ. of Colorado

G. Jeff Taylor, Univ. of Hawaii

Dan McCleese, JPL

David Beaty, JPL

Jonathan Lunine, Univ. of Arizona

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