Mars Water In-Situ Resource Utilization(ISRU) Planning (M-WIP) Study
April 22, 2016
Angel Abbud-Madrid, David Beaty, Dale Boucher, Ben Bussey, Richard Davis, Leslie
Gertsch, Lindsay Hays, Julie Kleinhenz, Michael Meyer, Michael Moats, Robert Mueller,
Aaron Paz, Nantel Suzuki, Paul van Susante, Charles Whetsel, Elizabeth Zbinden(affiliations in Appendix)

This “first-order” analysis of questions about supply-side planning related to potential water
resource deposits on Mars was jointly requested by NASA-SMD and NASA-HEOMD in Jan. 2016.
Recommended Bibliographic Citation:
Abbud-Madrid, A., D.W. Beaty, D. Boucher, B. Bussey, R. Davis, L. Gertsch, L.E. Hays, J. Kleinhenz, M.A. Meyer, M.
Moats, R.P. Mueller, A. Paz, N. Suzuki, P. van Susante, C. Whetsel, E.A. Zbinden, 2016, Report of the Mars
Water In-Situ Resource Utilization (ISRU) Planning (M-WIP) Study; 90 p, posted April, 2016 at
http://mepag.nasa.gov/reports/Mars_Water_ISRU_Study.pptx
Copyright 2016 California Institute of Technology. U.S. Government sponsorship acknowledged. All rights reserved.

Executive Summary (1 of 2)This scoping analysis is intended to provide guidance regarding a number of complex and interrelated issues involving the potential use of Martian water resources, and for which follow-up
action by a number of different entities would be beneficial.
• Objectives: 1). Formulate descriptions of hypothetical reserves on Mars, 2). Estimate therough order-of-magnitude of the engineered system needed to produce each of thereference cases, 3). Prepare a first draft analysis of the sensitivity of the production system
to the known or potential geological variation, 4). Prepare an initial description of thepreliminary implications for exploration.
• Reference cases: Four reference cases have been defined: Case A – glacial ice; Case B – anatural concentration of poly-hydrated sulfate minerals; Case C – a natural concentration ofphyllosilicate minerals; Case D – regolith with average composition as observed from in situ
missions.
• The ice case (Case A) appears to have certain advantages relative to granular materials(e.g. less sensitive to transport distance), but also some disadvantages (e.g. the need todeal with overburden). More study of the ice case is needed to put it on the same footing as
the granular materials cases (B-C-D).
• Of the granular materials cases (B-C-D), Case B would involve moving the lowest mass of
raw material, AND would have lower power requirements. Using regolith (Case D) would
require moving more mass (because it is lower grade), and would require more power toextract. Case C is intermediate.
4/25/2016

Water ISRU Planning, April 2016

2

Executive Summary (2 of 2)
•

•

•

•

Whether any of these cases is above minimum thresholds for a potential future human
mission depends on the resource envelope for that mission, as well as its architecture andpriorities—none of which has yet been determined.
The different cases have different sensitivity to known or potential natural geologic variation.
The granular materials cases (B-C-D) are most sensitive to the nature/scale of themechanical heterogeneity of the ore deposit, and the distance between the mine and theprocessing plant. The ice case (A) is most sensitive to the thickness and properties of theoverburden.
We do not have enough orbital or ground data to be able to determine if deposits as good or
better than the reference cases exist at Mars. Exploration is needed at several different
scales.
The details of the logic imply that this is a 2-step exploration problem—there needs to be anorbital reconnaissance mission followed by at least one landed exploration mission. The
details of how these missions are optimized is left to future study teams.
–•

This is needed to pick the landing site, whether or not we would be doing ISRU right away.

Follow-up work is needed in multiple areas, including technology development for ice andgranular mining cases, advance mission planning (including in both the human and therobotic arenas), improving our understanding of Mars, the geology, nature and mechanicalproperties of representative deposits, and in refining our exploration strategy from orbit andon the surface.
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Water ISRU Planning, April 20163

Objectives of This Study (Tasks)
1.

2.

3.

4.

Prepare an initial description of hypothetical “reserves” (identified, usable resource deposits*) that
may exist on Mars. Assume that these reserves are the output of an exploration program, and the
input to an overall engineering system. Specify all relevant parameters.
Estimate the rough order-of-magnitude mass/power/complexity of the ISRU engineered system(mining/acquisition, extraction, transportation, processing and storage) needed to produce a given
quantity of water from each of several categories of potential water “ore” deposits.
Prepare a sensitivity analysis of the major inter-relationships between geological attributes of thewater deposits (Task #1 above), and the engineering attributes of the production and processing
systems (Task #2 above), in order to propose preliminary minimum acceptable thresholds for“reserves”.
Prepare an initial description of the preliminary implications for exploration for the different reserves.
* The adjective "hypothetical" is assumed throughout these slides, modifying "reserves" from its legal meaning interrestrial mining practice (see Slide #10).

Introduction
to theProblem

Identify
Resources on
Mars, Establish
Reference
Cases

Engineering
Analysis of
Selected
Reference**
Cases

ExploreSensitivity ofEngineeringto Geology

Preliminary
Exploration
Implications**Primary focus was on water-bearing surface materials for a variety of reasons - Availability ofscientific & engineering data, initial survey of prior efforts, and others. Engineering evaluation of mid4/25/2016
latitude subsurface ice at the same level of detail is a key next step.

4

Key Antecedent #1: EMC(Evolvable Mars Campaign)

The Potential Benefit of Acquiring Local Water (1 of 2)
ISRU system
Landed Mass Comparison(ISRU Hardware + Propellant from Earth)
The ISRU system leverages the power andradiator systems that are pre-positioned by
the lander for human systems. So these are
not explicitly part of the ISRU system.
Total Mass, mt

Ratio: Propellant
produced per kg oflanded mass

ISRU for LOX &LCH4: Sulfates

1.6

22.1

ISRU for LOX &LCH4: Regolith

1.7

20.5

8.0

3.1

ISRU for LOX
only (no water)(1mt hardware + 7mt Methane)

Propellant only
(no ISRU)(24mt Oxygen + 7mt Methane)

31.6

These comparisons consider ISRU endto-end systems encompassing
excavation, resource processing andpropellant production, cleanup, andliquefaction.
For the LOX-only ISRU case, methane
would have to be delivered to Mars from
Earth.
These calculations only account for themass of the propellant that is needed in
the MAV. They do not account for the
additional propellant mass which would
be required to deliver that MAV
propellant to Mars from LEO. Thus theadvantage of a combined ISRU
LOX/Methane production system would
be greater than indicated.

naHarnessing even the lowest yield Mars regolith water resource for ISRU would offer a 6x
improvement over an LOX-only ISRU in the terms of the mass of propellant generated foreach kg of total ISRU system mass.
For every kg of total ISRU system mass delivered to Mars:– A Lox/LCH4 ISRU system can produce 20 kg of propellant– A Lox-only ISRU system can produce 3 kg of propellant

Key Antecedent #1: EMC
The Potential Benefit of Acquiring Local Water (2 of 2)•

The graph below compares ISRU systems for two different water resources and an
ISRU LOX-only (no water) system (which is the current architecture baseline).
– The masses are for the ISRU hardware only. While the water processing system masses are ~60%
greater than the LOX-only case, consider that the latter still requires 7mt of terrestrial Methane
each trip– The benefit of a higher yield granular resource is a power savings. The power required for case B is
comparable to the lox-only ISRU system.

66% >

54% >

42% >

4% >

Percentages
on the graphs
represent
comparison to
LOX-only
ISRU

Key Antecedent #2: HLS2•••

Human Landing Site Selection (HLS2): October 2015 workshop on Mars
Exploration Zones.
In addition to science regions of interest, all site proposers were asked to identify
one or more candidate water resource deposits within their Exploration Zone thathave the potential to produce 5 metric tons of water per year.
47 candidate sites proposed by the world’s leading experts in ISRU and Mars
geology. The four most common candidate water resource deposits
proposed include (not in priority
order):
1. Mid-latitude ice
2. Concentrations of polyhydrated sulfate minerals
3. Concentrations ofphyllosilicate minerals
4. Regolith.
See also ICE-WG (2015; Hoffman
and Mueller, co-chairs)

http://www.nasa.gov/journeytomars/
mars-exploration-zones
4/25/2016

Possible configuration of an Exploration Zone.
Note hypothetical “Resource ROIs” in gray.
Water ISRU Planning, April 20167

Ground Rules and Assumptions
1. A single surface location on Mars will be visited and explored by multiple crews (source:
EMC).
–

Implication: Site selection prior to any Mars missions must consider ISRU, even if ISRU is manifested later in the
campaign.

2. The site is equatorward of 50° latitude (source: HLS2).
3. The ISRU production window would be 480 days which would assume that the ISRU
system would arrive one mission opportunity ahead of the first crew, and produce allpropellant prior to crew launch.
–––480days = 26 month launch window – 9 month transit time – 1 month margin
This production timeline, baselined from DRA 5.0, is assumed to apply to any ISRU produced resources (LOXonly or LOX/LCH4).
This is a minimum production time since once the equipment is set up, there would be more time to produce
propellant for subsequent crews.

4. The ISRU system will be co-located with the ascent vehicle/habitat such that all ISRU
products can be delivered to and stored in the system that will use them.
––No separate storage is currently planned, implying that the utilization systems (e.g. MAV, habitat) arrive with or
before the ISRU system (as per DRA 5.0).
Excavation equipment delivers raw material to the ISRU system, where processing takes place. (Current
baseline – subject to future trades).

5. A nominal quantity of 16 metric tons of water per crew is assumed to meet therequirements of a fully fueled MAV and oxygen for crew life support.
6. Planetary protection constraints not considered at this time (see Slide #86).
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Water ISRU Planning, April 2016

8

The Exploration-Production Flow:
Introduction“Reserves” are the fundamental interface between
exploration and production (see Slide #12).
Some critical questions
1. How exactly would production interact with reserves?
2. Can we identify thresholds, above or below which
the proposed production system would not be
viable?
3. How would exploration discover and definereserves?

4/25/2016

Water ISRU Planning, April 20169

Confidence: The Concept of Reserves
Reserve
Classification

EarthApplication

Mars ISRU
Application

Confidence

ProvenUse as collateral
for a bank loan

Astronaut lives
can depend on it

99%

MAKE COMMITMENTS

Probable
Possible
Potential
4/25/2016

SPECIFIC
DEFINITIONSEXISTUNDEFINED

90%

UNDEFINED50%

THE EXPLORATION ARENA
Water ISRU Planning, April 2016

<50%
10

Definition of Reserves• Reserve is the raw material in-place, not yet extracted andprocessed but proven to be feasible to extract andprocess. Proven means the risk that the material is not present
as modeled, or is not extractable, or is not processable, issufficiently low (see practical definitions on Slide #10).
• Reserves are the output of the exploration process and the input
to the production process (see Slide #12).
• On Earth, reserves are proven using a feasibility study thatmeets a set of industry standards, generally including a pilot
program; and the risk is expressed in financial terms, forexample the interest rate on a bank loan one could get using the'reserve' as collateral.
• For Mars ISRU water, a future study team will need to define theset of NASA and mining industry standards that a feasibility
study must meet. NASA will define the acceptable level of risk.
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Water ISRU Planning, April 2016

11

The Exploration-Production Flow

outputUsableResource
Deposits

MINING

outputoutputAcceptable
Feedstock

UsefulRefinedProducts

A

B“Reserves” are the essential
interface between“exploration” and “production”
4/25/2016

PROCESSING

USABLE WATEREXPLORATIONPROVEN RESERVESCONCEPT

PRODUCTION
input

END
USER
C

From Beaty et al. (2016); discussion with the
Geological Society of Nevada acknowledged

Water ISRU Planning, April 2016

12

A Chicken-Egg Issue

Delineation of usable
reserves requires
knowledge of the
production system

Design of the
production system
requires knowledge ofthe reserves

Because of this chicken-egg relationship, both
exploration and engineering need to advance together.
4/25/2016

Water ISRU Planning, April 2016

From Beaty et al. (2016)13

Exploration Risk
Ease of Engineering
Requirements(Risk of Failing to Make an Acceptable Discovery)L

MED RISKHIGH RISKVERY HIGH
RISK

M

LOW RISKMED RISKHIGH RISKH

LOW RISKLOW RISKMED RISK

H

M

L

Quantity/quality of Data the Explorationists
are Able to Work with
FINDING #1. The more demanding the requirements for defining“reserves”, the higher the quantity/quality of data needed to make aminimally
acceptable discovery.
4/25/2016
Water ISRU Planning, April 201614

Task #1
Prepare an initial description of hypothetical“reserves” that may exist on Mars

Introduction
to theProblem

4/25/2016

Identify
Resources on
Mars, Establish
Reference
Cases

Engineering
Analysis ofReference
Cases

Water ISRU Planning, April 2016

ExploreSensitivity ofEngineeringto Geology

Preliminary
Exploration
Implications

15

Introduction: Reference Cases
1. Since both sides of the “reserves” interface are incompletely
defined (see Slides #11-13), the best way to proceed is bydefining a set of reference cases, and using them to evaluate
the relationships between “discoverability” and “producibility”.
2. The reference cases are all hypothetical—the question we areasking is “if discovered, would these be useful”?
–

The hypothetical cases are based on our current incomplete knowledge ofMars: We perceive there to be reasonable potential that deposits as goodas these exist (but discovering and defining them would take work!).

3. Once we understand the thresholds differentiating viable fromnon-viable, and the parameters that most matter for optimizing
the engineered system, the priorities for a logical exploration
program can be defined.

4/25/2016

Water ISRU Planning, April 201616

Definition ofReference Reserve Cases
Four reference cases were chosen to represent the output of HLS2 (See Slide #7)
Deposit Type
Essential Attribute

A. IceB. Poly-hydrated
SulfateC. Clay

D. Typical
Regolith (Gale)

Depth to top of deposit (stripping ratio)
Deposit geometry, size
Mechanical character of overburden
Concentration and state of water-bearing phasewithin the minable volume

variable (1-10m)

0m

0m

0m

bulk

bulk

bulk

bulk

sand

NA

NA

NA

–Phase 1

90% ice

40% gypsum1

40% smectite2–Phase 2–Phase 3–Phase 4–Phase 5-----23.5% basaltic
glass3
3.0% allophane4
3.0% akaganeite5
3.0% bassanite6
3.0% smectite2

3.0% allophane4
3.0% allophane453.0% akaganeite 3.0% akaganeite5
3.0% smectite2
3.0% bassanite6---

1. ~20 wt% water, 100-150°C
2. ~4 wt% water, 300°C
3. ~1 wt% water, >500°C
4. ~20 wt% water, 90°C
5. ~12 wt% water, 250°C
6. ~6 wt% water, 150°C

Geotechnical properties–large-scale properties (“minability”), e.g.
competence, hardness–fine-scale properties (“processability”) , e.g.
competence, mineralogy

The nature and scale of heterogeneity
Distance to power source
Distance to processing plant
Amenability of the terrain for transportation
Presence/absence of deleterious impurities
First order power requirementscompetent--hardsand--easysand--easysand--easy

no crushingneededno crushingneededno crushingneededno crushingneededvariation in
impurities±30% inconcentration±30% inconcentration±30% inconcentration

1 km

1 km

1 km

100 m

1 km

1 km

1 km

100 m

flat terrain

flat terrain

flat terrain

flat terrain

dissolved salts

none

none

perchlorate?

TBD

TBD

TBD

TBD

TBD

TBD

Note: PlanetaryProtection
implications are
addressed on
Slide #86

Not Considered
4/25/2016
PlanetaryProtection implications

TBDWater ISRU Planning,
TBD April 201617

Reference Reserves Notes
1.

2.

3.

4.

5.

Assume Case A consists of glacial ice underlying a sublimation lag, but isdivided into A1: an ice deposit mined by open pit methods, and A2: an ice
deposit mined by down-hole heating/recovery methods. The thickness of thislag is in the 1-10 m range limited by SHARAD measurements (See Slide #20.)
Future data sets and instruments can improve this precision.
For Cases B and C, assume that in a location where bedrock containing highconcentrations of these minerals exists, locations can be found where
weathering has disaggregated the rock into granular material.
The 4 wt% water noted for smectite in Cases B, C and D is the average wt%
water in a combination of Na- and Ca- forms; the average water content may behigher for some other types of phyllosilicates (see Slide #22).
The source data from Case D is explained in detail on Slides #23-25. Note thatthe “water” is inferred to be contained in three phases, two of which dehydrate
at 100C, and one of which dehydrates at >500C. We make the assumption (tobe reviewed) that material of this quality can be found at most/all candidate
landing sites without exploration. Since this material occurs “everywhere”,
transportation demands would be minimized.
Whether deposits better than these reference cases can be discovered anddefined is left as an exploration question (see Slide #62).

4/25/2016

Water ISRU Planning, April 201618

Basis for Case A
Map of Mars Glacial Features

With many of these glacier-related geomorphic features, we have no information
about whether residual ice remains, and if so, at what depth. Note that somelobate debris aprons have been confirmed to contain ice by radar investigations.
4/25/2016

Water2012;
ISRU Planning,
April 2016
From Dickson et al.,discussion
with Jim Head acknowledged19

Glacial Deposits on Mars:
More DetailMars: Lineated
Valley Fill

• Mars glaciers are covered with a combination of sublimation
till (the residue left as a result of ice sublimation) and rubble
from nearby exposed outcrops.
• SHARAD data show a single, discrete surface echo overglaciers, implying that the thickness of the protective
debris/dust cover is on order of the SHARAD verticalresolution (~10m) or less.
• Could be between 1-10 m thick• Glacial ice is 100s of meters thick.

Deuteronilus

200 kmImage credit: NASA/MSSS MOC

Mars: Lobate
Debris Apron

Image credit: NASA/JPL/UA HiRISE

4/25/2016

SHARAD data, showing the discontinuous nature of thicksubsurface ice in the middle latitudes. White line segments
indicate ice detections.
Water ISRU Planning, April 2016

Rummel et al. (2014) and Plaut (2016, Pers. Comm.)

20Basis for Cases B, C
Map of aqueous mineral detections
Note: footprint size is from 3x6km spots to 18-2000m/pixel
depending on instrument used for detection.

A master compilation of all mineral detections for Mars. Of relevance to this study are thephyllosilicate and sulfate detections.
From Ehlmann and Edwards (2014)
4/25/2016

Water ISRU Planning, April 201621

Basis for Case C
Phyllosilicate Water Content•

For the purpose of this analysis, we assume a deposit consisting of smectite with anaverage of 4 wt% water content – note that this is lower than would be expected for
terrestrial samples. It is also possible that phyllosilicate deposits with higher watercontents could be identified.

Equilibrium hydration state of Na- and Ca-smectites(left axis) and of Na-clinoptilolite (right axis) as afunction of T at a P (H2O) of 1.5x10−6 bars. Note thatat Mars surface conditions, Na-smectite has ~2 wt%
water, and Ca-smectite has ~7 wt% water.
4/25/2016

Modeled hydration maps for phyllosilicates in the
Mawrth Vallis region. These regions exhibit watercontents 2–3 times higher than surrounding terrains
with similar albedo values, approaching values of
6–9 wt.% H2O.

From Bish et al (2003) (left),
Milliken
etAprilal (2007)(right), and discussion withWater
ISRU Planning,
2016
Dave Bish and Ron Peterson

22Basis for Case D (1 of 3)
Introduction to the Martian Regolith•

The broadest definition of “regolith”, as it is used in a planetary sense, is: “Theentire layer or mantle of fragmental and loose, incoherent, or unconsolidated
rock material, of whatever origin (residual or transported) that nearly
everywhere forms the surface, and that overlies more coherent bedrock.” Assuch, this term as applied to Mars encompasses “soil”, dunes, talus, ejecta,
rubble, airfall dust, etc.

Rocknest, MSL
Bagnold, MSL

JPL/NASA

Endurance, Opportunity

Ares Valles, Pathfinder

Paso Robles, Spirit
Although regolith, in the strictest sense, is present essentially everywhere on Mars, it is not all
equally amenable to ISRU operations. Note significant differences in mechanical properties.

Basis for Case D (2 of 3)
What is the Regolith Made of? (Data from MSL)••

Mineralogy and total weight percent water used for reference Case D are based on data from MSL
instruments: CheMin, SAM, and DAN.
Case D mineralogy was based primarily on Rocknest, with additional minor components from John
Klein and Cumberland to match the 1.5 wt% water indicated by the more conservative DAN results.
http://photojournal.jpl.nasa.gov/jpeg/PI
A16225.jpg

Crystalline and amorphous components (wt%) of the John Klein and Cumberland
drill powders, compared with the Rocknest scooped eolian deposit. From plagioclase
to pyrrhotite the estimated errors are ~6% of the amount shown for abundances of>20%, ~15% for abundances of 10 to 20%, ~25% for abundances of 2 to 10%, and~50% for abundances of <2% but above detection limit. Phases marked with anasterisk are at or near detection limit. Relative 2σ errors are ~50% of the amountshown for smectite and ~60% for the amorphous component. [Data primarily fromCheMin, with smectite information from SAM.]
4/25/2016

Water ISRU Planning, April 2016

From Vaniman et al. (2014)

The Rocknest
sample (MSL)
This material was analyzed indetail by MSL.
24

Basis for Case D (3 of 3)
DAN Measurements of Water Equivalent Hydrogen••

DAN measures total hydrogen over a footprint 3m wide and down to a depth of ~60 cm.
Data from DAN are best modeled by a 2-layer structure•
Upper layer has less H (average 1.5-1.7% WEH) than the lower layer (average 2.2-3.3%
WEH).
•
Local anomalies as high as 6% WEH were measured in the first 361 martian sols; in later sols
contents up to 10% WEH were measured.
Data from MSL’s DAN
instrument are bestmodelled using a twolayer subsurface
structure. The top layer
ranges between 10-30
cm thick. Water
concentrations are intable below.

Note that the DAN instrument detects H, notwater. The H could be present in hydrous
minerals or as OH—it is almost certainly notpresent as liquid water. The “water-equivalenthydrogen” or WEH measured by DAN, is used to
calculated the potential amount of “water” present
using the models.
4/25/2016

Water ISRU Planning, April 2016

From Litvak et al. (2014) (top) and Mitrofanov et al. (2014) (bottom).

25

Other Options Considered and Ruled Out:
Extraction of Water from the Atmosphere
Some general facts and calculations:
1. At Mars surface pressure = ~6 mbar; atm density averages ~0.020 kg/m3, water ~210 ppm =0.0042 g(water)/m3
2. 1 kg water is contained in 250,000 m3 of atmosphere
3. To produce 5 mt water per yr, 0.57 kg would have to be produced per hour, which means 2400m3 (~1 Olympic sized swimming pool) of atmosphere would have to be handled per minute,assuming 100% recovery. This is equivalent to 84,000 CFM.
4. Martian atmosphere is at 1% of the pressure of the inlet pressure for compressors on Earth, thus
an additional compression factor of 102 would have to be applied to get the same throughput.

 We have not seen a credible method proposed forseparating the water from an airstream of this scale,so we cannot estimate recovery efficiency.
 The air-handling system implied by these calculations
would be on the same order of magnitude as thelargest air compressors known on Earth: ~600,000
CFM, requiring 65 megawatts to run, and roughly
5x5x10m in size.

AR140 MAN1 – thelargest axial flow
compressor for use inindustrial applications(on Earth)

CONCLUSION: The mass, power, volume, and mechanical complexity of the systemneeded for this approach are far outside of what is practical for deployment to Mars.
4/25/2016

Water ISRU Planning, April 201626

Other Options Considered and Ruled Out:
RSL, Permafrost, High Latitude Ice
Recurring Slope Lineae (RSL)– Only occur on steep slopes – very difficult for mining/transport operations.
– By definition, RSL are transient (seasonal). If liquid water is present, it may be only temporary.
– Hydrated minerals likely present, but are not necessarily more concentrated than in our othercases.
Image of a set of RSL(dark streaks) on acrater wall. Image credit
JPL/NASA/Univ. Arizona

Permafrost: Although this exists (at high latitudes) on Mars, permafrost represents theexistence of ice in the pore space of rock or soil, which is a low-grade variant of Case A(glacial ice). Since this will be less productive than glacial ice, we evaluate the latter here.

High Latitude Ice: Although large deposits of ice exist on Mars above 60° latitude, theseexceed the latitudes set by our ground rules and assumptions (see Slide #8).
4/25/2016

Water ISRU Planning, April 201627

Other Options Considered and Ruled Out:
Deep Groundwater (1 of 2)• MARSIS and SHARAD (radars) would be able
MARSIS SHARAD
to detect Mars groundwater (liquid water or
Coverage~69%~31%
brine in Mars bedrock) if it were present within
Spatial res. ~10 km~0.5 kmthe depths cited.
• No such groundwater has been detected.

Depth res.

~100 m~10 m

Max depth~1 km~ 300 mMARSIS COVERAGE, NOV. 2015

4/25/2016

Map of Mars
showing MARSIS
data coverage as of
Nov. 2015.
• Yellow: Survey
completed and nowater detected(evidence ofabsence).
• Red: No data or
SNR too low(absence ofevidence)

Water ISRU Planning, April 2016

Contribution from Jeff Plaut; discussion with Rich Zurek, Serina Diniega

28Other Options Considered and Ruled Out:
Deep Groundwater (2 of 2)
Atmosphere
Ground surface
The absence of radar reflections from below
ground surface indicates no water table

Subsurface• Confident about lack of liquid water within upper 200-300m,
where signal is strongest.
• Below this depth, signal strength is too weak to determine
presence or absence of water.
Image credit: ASI/NASAVERTICAL POSITION

Radar energy from orbit

MARSIS 5-MHz, radargram of the Athabasca region of Mars (4-7N, 149E). Images are taken along
the track of the orbiter, using radar to detect subsurface features like water, which would show up asa reflective surface.

•

Given the absence of detections, and the fact that the coverage map is rapidly filling in  unlikelythat there is groundwater at a depth shallower than ~200-300 m anywhere on the planet.
4/25/2016

Water ISRU Planning, April 2016
Contributions
from Jeff Plaut; Rummel et al. 201429

Task #2
Estimate the basic engineering attributes ofthe potential production and processing
ISRU systems

Introduction
to theProblem

4/25/2016

Identify
Resources on
Mars, Establish
Reference
Cases

Engineering
Analysis ofReference
Cases

Water ISRU Planning, April 2016

ExploreSensitivity ofEngineeringto Geology

Preliminary
Exploration
Implications

30

Introduction to the Engineering
Analysis• A NOTE ABOUT UNEQUAL DATA. Although both granularmaterials (Cases B-C-D) and ice cases (Cases A1 & A2) areconsidered in this section, more prior work has been done on theformer which enabled analysis in greater detail at this time. We
would like to see further analysis of the latter to bring these tocomparable levels of understanding.
• In addition to the overall Ground rules and Assumptions (Slide#8):– Infrastructure assets would be pre-deployed ahead of crew mission:
Power systems (10’s of kW), Mars Ascent Vehicle (unfueled), ISRU
processing plants, off-earth mining excavation equipment (rovers).
– MAV fuel production must be completed between arrival of MAV at
Mars and departure of crewed mission from Earth [desire to know
MAV has been successfully fueled before committing crew tolanding on Mars] (~480 sols available)*Note: “mt” used for metric ton throughout (1,000 kg)
4/25/2016

Water ISRU Planning, April 201631

Granular Materials Cases:
Pre-deployed ISRU ”Enterprise”
Power Source(e.g. 4x 10 kW fission reactors)

MAV Cabin
Methane Tank
LOX Tank
Fuel Plant
Water Plant

Local regolith fields(larger or smaller depending on
Processing temperature)
4/25/2016

Remote Gypsum-rich
deposits

Remote Smectiterich deposits

Excavators deliver ore,
Remove spent tailings

Water ISRU Planning, April 201632

Fuel Processing

19 mt
40 kg/sol

Water
16 mt

Propellant
Processing

33 kg/sol

Local Power Source(e.g. Fission Reactors)

Methane
7 mt
15 kg/solLOX
28 mt*
58 kg/sol~20 kW• Combines with 19 mt of
atmospheric CO2 togenerate Methane & LOX

CO2• To generate MAV
propellants, total of 16 mt ofwater would need to bedelivered/processed in 480
sols available (33 kg/sol)*Note: only 23 mt required for MAV propellant.
Balance available for crew or other uses
4/25/2016

Water ISRU Planning, April 201633

Ore Temperature Processing Choice• Water available from various feedstocks is a function of thetemperature at which ore is processed.
• For hypothesized deposits, processing temperatures would beselected where “most” of water is extracted at lowest reasonabletemperature / power points.
• For typical martian regolith, two scenarios considered, based on
two dominant mineral phases (see following).
– Hypothesis: Lower temperature processing may require more
feedstock, but might result in less power required.
– [Note: Upon analysis, this hypothesis was subsequently provenfalse – processing greater mass of ore in same amount of time
resulted in roughly equivalent power required.]– Additionally, regolith processing temperatures above 450 C may
release corrosive contaminants which may be harmful to equipment
for diminishing returns of water.
4/25/2016

Water ISRU Planning, April 201634

Water Abundances by Feedstock/Temperature
Gypsum-rich

4/25/2016

Water ISRU Planning, April 2016

Smectite-rich

Typical Martian Regolith

35Energy Calculation Method• Feedstock definition (specifically, water availability perprocessing temperature) used to determined mass of each typeof ore needed to achieve water production target.
– Assumed 75% efficiency of water removal from ore.

• Calculated heat necessary to raise ore temperature to
dehydration temperature and added heat of dehydration.
DH = m cp DT + DHdehydration• Current analysis assumes heat loss to calcination reactor is negligible
compared to heat required to raise ore temperature (i.e. thin walled, wellinsulated) [Assumption may need to be revisited in future work].

• Power Required = DH / time
– Calculated for both continuous processing and “batch-mode” –essentially same power required with either calculation.
– Batch mode assumed two hours to heat up each batch of ore.
4/25/2016

Water ISRU Planning, April 201636

Key Characteristics by Feedstock
2500

10
Total_regolith_needed, mt
Total_processing_power, kW
Assumptions: 480day processing time, 16MT waterrequired (MAV propellants),Continuous soil reactor at 100%
heating efficency.

2000

9
8

Total Regolith needed, mt

1500

6
5

1000

4
3

500

Water volatilization power, kW

7

2
1

0

0
D1, Typical @ 150C••

D2, Typical @300C

B, Gypsum @ 150C

C, Smectite @ 300C

Gypsum deposits would have the lowest mass AND power requirements of the granulardeposits. Ice mining power not established due to less experience and available data.
Typical martian regolith processed at low temperatures doesn’t result in lower power(due to production rates) AND requires more mass -> NO ADVANTAGE
4/25/2016

Water ISRU Planning, April 2016

37

RASSOR Key Characteristics
Key Characteristics Assumed:• Excavator capacity: 2 x 40 kg drumsof granular material

Baseline hardware design of NASA KSC-developed
RASSOR Prototype Excavator - key characteristicsof this reference model have been used forpreliminary sizing analysis. For additional
information about this prototype, contact Rob
Mueller.

4/25/2016•

Traverse speed: 25 cm/s•

Battery powered – recharge inproximity to power source•

Duty Cycle / Recharge: 60% onduty, 40% off-duty [Battery powered– recharge at plant site]

Water ISRU Planning, April 201638

End-to-end Process Flow
Ore Processing

Case D1:

Typical Martian Regolith(2,000 mt)~4150 kg/sol
Case D2:**OR****OR**

Smectite Clay-enriched
Regolith (583 mt)

19 mt**OR**

Ore->Water(@425 K)

~390 kg/sol~2 kW

33 kg/sol

40 kg/sol

Water
16 mt
33 kg/sol

Water ISRU Planning, April 2016

15 kg/sol

LOX
28 mt
58 kg/sol~25 kW

Local Power Source(e.g. Fission
Reactor)
4/25/2016

Methane
7 mt

Propellant
Processing

Gypsum-enriched
Regolith (186 mt)

Ore->Water(@575 K)
~5 kW

~1200 kg/sol
Case B:

CO2

~8 kW

Case C:

Ore->Water(@575 K)

~8 kW

Typical Martian Regolith(1,250 mt)~2600 kg/sol

Ore->Water(@425 K)

39

Intro to Excavation/Travel Analysis
Ore for
16 mt of H2O

Integrated timeline analysis
conducted based on amount ofore required, time required for
excavator loading/unloading,
Period 2
traverse distances / rates &Excavation Zone
time available

Period 3
Excavation Zone

Ore for
16 mt of H2O

Ore for
16 mt of H2O

Period 1
Excavation Zone
Repeated Excavator Trips

Each trip excavates and dumps twice (ore & spent feedstock)
24.5 hours operational time / Mars day (Sol)
16 mt of H2O needed in 480 sol excavation Period
Material is granular uncemented material

4/25/2016

Water ISRU Planning, April 2016

[Variable distance: 100 m(local) up to ~several km fromprocessing plant ]40

Summary of Excavation/Travel Analysis
Case

Mass of Ore
Required(metric tons)# RASSORclass loads (@80kg/load)Distance from
Ore to Plant,
typical# RASSOR – class
Excavators used (@60% On-Duty)

Duration Required(sols, <480available)

D1 – Regolith@425K~2,050 mt>25,000~100 m3 excavators

382 sols

D2 – Regolith @575K~1,270 mt>15,800~100 m2 excavators

350 sols

C – Smectite(proximity)~580 mt>7,000~100 m1 excavator

318 sols

B - Gypsum~185 mt>2,000~100 m1 excavator

88 sols

B - Gypsum(same)(same)~1,200 m

1 excavator

480 sols

B - Gypsum(same)(same)~3,000 m

2 excavators

453 sols• Multiple excavators would be required for typical martian regolith cases (three for D1/two for D2)• D1 / D2 assumed to be feasible at “any” location (i.e. transportation always ~100m)• Single excavator could handle hydrated minerals in local proximity• Smectite would be feasible <100m from lander (318 sols), distances >100m would require >1 excavator• Pair of rovers could handle gypsum at distances of up to 3 km (same as D2 in local proximity to plant)
4/25/2016

Water ISRU Planning, April 201641

Area Required (at 5 cm depth*)
Mass (kg)Volume (@2t/m^3)

Area (at0.05 mdepth)

FootballFields (@5400 m^2)

186,047

93

1,860

0.3

Smectite

583,942

292

5,839

1.1

Regolith@300

1,269,841

635

12,6982.4

Regolith@150

2,051,282

1,026

20,513

3.8

Gypsum
(@40%)

GypsumRegolith(@300 C)

Regolith(@150 C)

Smectite(@40%)

Caveats:• These areal estimates presume anerosional deposits configuration that is
broad but relatively thin (homogenous
on at least ~5 cm scale)• Actual depth could be greater or
lesser depending on nature ofdeposits and vehicle design. Also, fordeeper deposits, option exists to
excavate multiple shallow layers withrepeated trips to same site.
4/25/2016

Bulk Density Heuristics Used for Analysis:
0% porosity minerals (“rocks”): ~ 2.7-3.3 g/cc (3 +/10%)
35% porosity “undisturbed” granular deposits: ~ 1.8-2.2
g/cc (2 +/- 10%)50% porosity “disturbed” (extracted) granular material:~1.35-1.65 (1.5 +/- 10%)c.f. Water = 1.0 g/cc, terrestrial sand= ~1.6 g/cc
*5 cm excavation depth assumed based on RASSOR demonstrated
capability to date (originally designed for lunar scenario).

Water ISRU Planning, April 201642

Granular Mineral Deposits:
Engineering Summary (1 of 2)
1. Although regolith (in some form) is present almost everywhere on Mars, it is not yet
known how common are deposits that meet all of the specifications to be classifiable asminable “reserves” (this is an exploration question).
2. It would be ideal if the mine could be established in the immediate vicinity of the lander,
allowing for short-range excavators which could leverage power, processing andstorage at the lander site. Transportation distance would be a major driver in thesescenarios.
3. Regolith is comparatively low grade (~1.5% WEH), and it consists of multiple diverse
components that release their water at a variety of temperatures. Recovering somewater would be possible at relatively low-T, but recovering all of the water would
require high-T (with the possibility of additional released contaminants).
4. Polyhydrated sulfate deposits would have BOTH a lower decomposition temperature,
AND a higher water content, than clay mineral deposits. However, it is unknown howeither of these would compare to a specific regolith deposit.

FINDING #2. Three different types of granular mineral water deposits(Cases B, C and D) may have similar implications for acquisition, butfavorability from the point of view of extraction is (accumulations ofpoly-hydrated sulfate minerals, clay accumulations, and typicalmartian regolith with ~1.5% WEH).
4/25/2016

Water ISRU Planning, April 201643

Granular Mineral Deposits:
Engineering Summary (2 of 2)
5. Higher grade mineral deposits are likely to be sparsely
distributed (see Slide #72), and this may imply larger
transportation distances for the rovers (a significant negative
consequence) or may control the base location (giving lessfreedom in the layout of the human exploration zone). However,
the higher yield of high-grade deposits would reduce batch
sizes, and total volume of raw material to be moved—asignificant advantage in mass and power. The trade-off
between these needs to be evaluated in more detail.
FINDING #3. A key trade-off between regolith and higher-grade
mineral deposits: The latter are likely to be locally distributed (andthus may be associated with larger transportation distances), and theformer would require moving and heating larger masses of raw
material.
4/25/2016

Water ISRU Planning, April 201644

Engineering Notes on Case A•

Although Case A (buried glacial ice deposits) may represent the mostconcentrated source of water, work during this study was hampered by
the relatively low amount of recent engineering research conducted inthis area.
– Recent emphasis has been on near-surface approaches more applicable on Moon or innorthern permafrost regions on Mars (>50° from equator)•

Candidate Strategies for deeper ice (>1m) include:– Surface mining of ice: Remove overburden, extract solid ice [Preliminary
Analysis Conducted herein] or– In Situ Recovery: Drill through overburden, melt/dissolve ice at depth andrecover/separate at surface [Not analyzed in this study– See Slide #82]

“Cryobot” for
Science
Exploration(earlier concept)

Near-Surface“Mobile In Situ
Water Extraction(MISWE)”
Credit: K. Zacny, Honeybee Robotics
4/25/2016

Water ISRU Planning, April 2016

Credit: NASAJPL (1999)
45

Overburden removal for an Open Pit
Over Ice
Overburden:
+

10°

45°
(repose)Analysis conducted to compare mass/volume ofoverburden to be removed for subsurface ice (toenable surface mining of ice)
Q: At what ice depth does overburden
mass/volume exceed mass/volume required forother granular cases (B-C-D)?

Ramp(access)

TBD Depth(solve for)

Pit

•

•

2.0 m
Ice overburden removal vs regolith direct

8.5 m

3000.0Ice at 2.2 m = Case B - Gypsum
Ice at 3.7 m = Case C – Smectite ClayIce at 5.2 m = Case D2 – High Temp Regolith
Ice at 6.4 m = Case D1 – Low Temp Regolith

Subsurface Ice:
17.4m3 required for 16t water= 8.5m (l) X 1m (w) x 2.0m (d)(width based on notional excavator geometry)

2500.0Tonne / 480 Sols

2000.0Notes/Caveats:•
Does not take into account the potentiallymore difficult excavation of ice-regolith
mixtures.
•
Overburden removal disturbs the thermal
equilibrium which may lead to ice
subliming away over time.

ramp & overburden mass
Case D1

1500.0Case D2
Case C
1000.0Case B

500.0

0.0
0

1

2

3

4

5

6

7

8

Depth of Ice from Surface (ice concentration 90%)

4/25/2016

Water ISRU Planning, April 201646

Subsurface Ice – A 2nd Possible
Concept of Operations•••A) Initial landed assets arrive (MAV, ISRU Plant,
Power Source) including rover carrying drilling +cryobot equipment (Mobile Drilling/Transport Rig= MDTR)
B) MDTR traverses to the buried ice depositC) MDTR drills through the overburden (may or
may not need to “case the hole” while drilling)
–

•

•

•

“Cryobot” heat probe may either be part of drilling operation,or lowered down the shaft after ice is reachedD) Once ice layer is reached, cryobot is heated,
ice melts/sublimes – cold-trapped in “hood” over
“hopper” onboard rover at surface
E) Once MDTR hopper is filled with ice, rover
returns to MAV/Fuel plant. Hopper full of ice is remelted & processed.
F) MDTR returns to buried ice deposits for as
many round trips as necessary.

Full implications of drilling + melting not examined forthis study – see Follow-Up Work Slide #82
4/25/2016

Water ISRU Planning, April 2016

Drill
(retracted)
MDTR Vehicle

winch
Recovery
Hood - H20

Ice Hopper
Cold trap

Overburden“Cryobot”
Heat Probe

Subsurface Ice

Schematic illustration of a possible
down-hole water recovery system.

47

Subsurface Ice Deposits:
Engineering Summary
1.

2.
3.
4.
5.

Accessing subsurface ice deposits using a small open pit would require significant removal of
overburden. The mass to be moved would go up geometrically with depth to ice, and thebreak-even point appears to be not more than a depth of burial of 2-3 m.
The mechanical acquisition of hard ice could be difficult, especially if there are entrained
rocks/sand. Higher excavation energy may be required than for granular materials.
Once exposed, the ice deposit would be unstable. The rate of this process has not beenmodeled, so we don’t know yet if this has a practical significance.
Methods to collect volatiles in-situ (e.g. down-hole processing) are potentially attractive, but
are low TRL and may have complications due to the creation of an underground void.
Because the raw material would have a higher concentration of water than any of themineral-based possibilities, the mass to be transported would be lower, and thustransportation distances could be larger. In addition, the processing could probably be
operated with higher yield, lower power, fewer batches/cycles.

FINDING #4. Significant engineering challenges may be associatedwith mining buried glacial ice. If these challenges could be resolved,
the subsurface ice cases (A1 & A2) would involve less mass andenergy for transportation and processing compared to any of themineral cases (B-C-D).
4/25/2016

Water ISRU Planning, April 201648

Key Factors in Comparing Cases••

Summary Table Generated to Compare Cases (see following)
For each case (row), the following attributes are characterized:– Type of Ore Considered (Gypsum-rich (Case B), Smectite-rich (Case C), Typical Martian Regolith(Case D))– Excavation/Extraction Strategy– What is the equipment needed to removed the ore or overburden
from its original location? For typical martian regolith: Processed at low temperature or high?
– Ore processing temperature & power – What are the specs for the processing systems for the
method selected?
– Transport to processing plant – What must be transported to a processing location, and how far?
Can the plant potentially be located at the site of the resource?

– Ore/tailings mass per mission – How much mass of the given ore is needed for each human
mission? How to dispose of equivalent mass of spent tailings?
– Transport to fuel plant – What is the equipment needed to transport the raw ore to a fuel location?
– Fuel processing – what power is needed for converting water + atmospheric CO2 into
LOX/Methane?

4/25/2016

Water ISRU Planning, April 201649

Summary of Key Factors
Landing
Proximity

Excavation/E Ore/Tailings Transport to
xtraction
Mass per Refinery/RetoApproach
Missionrt

Land onBatch
Excavation
Rovers300 C /
~1,300 tons Not Required
CommonContinuous or Not required(@1.25%)/Minimal(~20 kW)
Batch (8 kW)~28 kW1

Land onBatch
Excavation
Rovers150 C /
~2,000 tons Not Required
CommonContinuous or Not required(@0.75%)/Minimal(~20 kW)
Batch (8 kW)~28 kW1

Clays

Surface Mining, ~several km
Central Processing from base

Batch
Excavation
Rovers~600 tons(@3%)

Ore Transport
300 C /
CommonRover (~600 Continuous or Not required(~20 kW)
tons)
Batch (5 kW)~25 kW1

Hydrated
Sulfates

Surface Mining, ~several km
Central Processing from base

Batch
Excavation
Rovers~200 tons(@9%)

Ore Transport
150 C /
CommonRover (~200 Continuous or Not required(~20 kW)
tons)
Batch (2 kW)~22 kW1[FUTURE
WORK]:
Subsurface Ice

Surface Mining

Deposit

Regolith

Regolith[FUTURE
WORK]:
Subsurface Ice

Strategy
Surface Mining,
Central Processing(higher temp,
lower mass)
Surface Mining,
Central Processing(lower temp,
higher mass)

Down-hole heatprobe + In Situ
RecoveryRefinery /RetortTransport to
Fuel
Fuel Plant Processing

Total Power1
Estimate(Summary)~several kmfrom baseProhibitive
beyond TBD Not required Not required
meters?

Ice Transport
CommonRover (16(~20 kW)
tons)

TBD (field)+ ~20 kW~several kmfrom base

Drill / Kerf
Subsurface
only,
heating, Gas- Ice Transport
CommonDownhole Not required Not required phase Recovery Rover (16(~20 kW)
with cold trap
"Cryobot"
tons)(TBD kW)
heat probe

TBD (field)+ ~20 kWNot required

1 Total power
4/25/2016
Water ISRU
April 201650
does not include power to load and transport feedstock
onPlanning,a transporter.
Power for feedstock extraction are idealized power levels

without efficiency losses. If efficiency losses are added in difference between options will likely be greater and potentially, significantly greater.

Blasting and Crushing
1. Comminution (blasting, crushing, and grinding) is used on a wide variety of rockores on Earth. These technologies color how we think about “production” (seeSlide #12). Should we think about their specific application to water production atMars?
2. For water-bearing minerals on Mars (Cases B-C-D), natural long-term weathering
processes may have resulted in materials in granular form in suitableconcentrations. If these deposits can be found, blasting will not be needed.
3. Crushing and grinding typically are used to raise the recovery efficiency in theprocessing plant. For Mars, we are assuming a recovery method consisting
simply of heating/vapor capture. For materials under consideration in this study,
grain size has less effect on water recovery than traditional experience onterrestrial ores.
4. Blasting, crushing, and grinding are complex processes – they require significant
mass, power, and equipment with many moving parts (and by inference, highmaintenance and low reliability).

CONCLUSION: For these reasons, we assume that comminution is neither
necessary nor effective as a part of the Mars water production scenario. We
encourage this assumption be challenged by future study teams.
4/25/2016

Water ISRU Planning, April 2016

51

Task #3
Prepare a sensitivity analysis of the major
dependencies between the engineered
systems and known or potential geologicalvariation
Introduction
to theProblem

4/25/2016

Identify
Resources on
Mars, Establish
Reference
Cases

Engineering
Analysis ofReference
Cases

Water ISRU Planning, April 2016

ExploreSensitivity ofEngineeringto Geology

Preliminary
Exploration
Implications

52

Dependencies of Engineering on
Natural Geological Variation• Several attributes of the natural geological variation of thedeposits represented by the reference cases (Slide #17) havethe potential to exert a significant influence on the engineeringarchitecture. Choosing and optimizing a specific engineering
design is therefore dependent on knowledge of these properties.
The following appear to be of greatest importance:
1.
2.
3.
4.
5.
6.
7.

Geometry, size, location, accessibility of the ore deposit
Chemical properties (“processability”) of the ore deposit
Nature and scale of ore heterogeneity: mechanical consistency
Nature and scale of ore heterogeneity: water concentration
Thickness of overburden
Mechanical properties of overburden
Distance between the deposit and the processing plant• Evaluating these dependencies in more than a qualitative way
is deferred to future studies.
4/25/2016

Water ISRU Planning, April 201653

Geometry, Size of the Ore Deposit
1. Knowledge of the specific geometry and size of the deposit isdeemed to be associated with significantly less risk for Cases A, D.
a) For glacial ice (Case A), the natural scale of glaciers is far larger (seeSlide #20) than the minimum required production of 16 mt (Slide #8).
The chance of discovering a glacial ice deposit that would yield lessthan 16 mt is effectively non-existent.
b) For martian regolith (Case D), the assumed properties may begeneric enough that if appropriate regolith is present at all, it will be ina quantity >>>16 mt.

2. For Cases B and C, the deposits represent more highly
concentrated occurrences. Until we understand better the specificprocesses that have created these hypothesized concentrations,
we have poor ability to predict the form and the amount of materialpresent in a minable configuration.

4/25/2016

Water ISRU Planning, April 201654

Nature and Scale of Ore Heterogeneity—
Mechanical Consistency (1 of 2)
Given the kinds of mining and processing systems described in Task #2,
several aspects related to the mechanical consistency of the ore have thepotential to cause difficulties that would reduce the efficiency of the waterproduction system:• Cases B-C-D: Many kinds of granular material deposits consist of unevenparticle size distributions that include significant amounts of smaller andlarger sizes than the process-optimum.
oooThe abundance, and variation in size, of rocks is
an issue that can be dealt with by the
choice/development of mining method. The
presence of even a few very large boulders would
sanitize a portion of the deposit, but a welldesigned excavation sequence in space and time
would minimize this impact.
Over-sized material (rocks) wedging in hardwareand clogging the process flow would reduce waterproduction rate and shorten equipment life.
Under-sized material (fines) lost during excavationand transport could reduce water production rate
to a degree depending on the process used.
4/25/2016

JPL/NASA

Dingo Gap (MSL)
Note significant variation in mechanicalproperties of the regolith across this image.

Water ISRU Planning, April 201655

Nature and Scale of Ore Heterogeneity—
Mechanical Consistency (2 of 2)• Case A: Glaciers are well-known for having entrained
rocks/gravel/sand. In our definition of Case A, we assumed 90% ice,and 10% entrained other material. That proportion can vary widely innatural glaciers, as can the size of these rocks. The
choice/development of mining method will determine the effect ofentrained refractory material (rocks) on the process efficiency.
From Arvidson
et al. (2009)

Rock embedded
in ice on Earth

Glacier on Earthw/ rock debris
The ice at the PHX landing site wasfound to be very hard.
4/25/2016

Dealing with glacial ice may require astrategy to deal with associated rocks.
Water ISRU Planning, April 2016

56

Thickness and Mechanical
Properties of Overburden
1.

2.

3.

Case A1 involves the removal of overburden to create a small open pit(Slide #46). Thus, the quantity and mechanical properties of the material
to be moved make a very important difference in the viability of thisdeposit type. This material could be referred to as a “sublimation lag
deposit”, and such materials can be notoriously heterogeneous withrespect to properties like particle size distribution (mixed or cemented ice,rock and sand), shape, and composition.
For Case A2, the amount of overburden to be moved or drilled through issignificantly smaller than for A1, but the concept is completely dependent
on creating an opening through which the glacial ice can be accessed(Slide #47). This may induce ground stability complications (both holeand cavity) that may or may not be amenable to engineering control.
For Cases B-C-D, it is assumed for now that no overburden needs to be
moved.

Note: Slide #18 has more notes on the reserve reference cases.
4/25/2016

Water ISRU Planning, April 2016

57

Distance Between Mine and Plant
1.

2.

3.

In Case D, the mass of the material to be moved is the largest (see Slides#42-44), so this scenario has the greatest sensitivity to travel distance fromthe mine to the processing plant. Fortunately, these deposits appear to be
the most widespread, so the opportunity to choose sites that are closeenough to each other may exist. With distances > 100-200 m, this casequickly becomes unfavorable.
The ore deposits in Cases B and C are expected to be more localized, and“rarer” (see Slide #72), but since the grade is higher (and thus less ore massis required), more distance could be justified.
For Cases A1 and A2, only water in the form of ice or liquid would need to betransported. This would significantly reduce the transportation challenge.
However, since it may be undesirable to place other necessary facilities(Hab, MAV, power plant, etc.) with foundations above glacial ice, and this ice
is likely to form in areas with significant topography, this may increase
distance, though this may not be an issue due to the reduced volume mined.

Cases D and C might be optimized with a larger excavator than has been considered inthis study. However, this would come with a penalty in mass for a larger excavator.
4/25/2016

Water ISRU Planning, April 201658

Traversability• Traversability for mining requires nearly-identical trips to bemade many times (the variation arises within the mining area,
which constantly changes configuration). For mines on Earth,haul-road design is limited to very small variations for economic
reasons. We need to design a transportation system that canreliably and quickly travel almost the same route over and overon auto pilot.
• Loose regolith can cause loss of traction. Excavation andtransport will loosen the regolith in concentrated areas, causing
potential trafficability issues. Must design roads, vehicles, or
mining method to address this issue.
• Note however, that since the assumption is that regolith iseverywhere, this is more an engineering problem than an
exploration problem.
4/25/2016

Water ISRU Planning, April 201659

Other Dependencies ofEngineering on Geology
1. Ore deposit chemical properties – the complexity and energy
requirements for the production system are much higher for Case D,
and moderately higher for Cases B and C, than for Cases A1 or A2 (dueto diversity of both mineralogical and mechanical properties).
2. Ore deposit water concentration – since Case D involves processing
significant amounts of material, a deposit where the grade is abnormally
low could be a very high risk to the mission. This is important for Case B
and C as well, but less so.

Additional factor affecting engineering conclusions, but notassessed:•

Impurities – certain types of impurities potentially present in any of thecases could be damaging to the processing system or generate
unwelcome byproducts.

4/25/2016

Water ISRU Planning, April 201660

Dependency of Engineering
Conclusions on Variations in Geology
Relative Importance of Knowledge
Row # Characteristic
1

Geometry, size of the minable ore deposit

A1:

A2:

B: C: D:

Ice
(Open Pit)

Ice
(Subsurface)

Hydrated
SulfateClaysRegolith

L

L

M

M

L

Chemical properties (“processability”) of
the ore deposit
Nature and scale of ore heterogeneity:mechanical consistency

L

L

M

M

H

H

H

H

H

H

4

Nature and scale of ore heterogeneity:water concentration

L

L

M

M

M

5

Thickness of overburden

H

M

n/a

n/a

n/a

6

Mechanical properties of overburden

H

M

n/a

n/a

n/a

7

Distance between the deposit and theprocessing plant

M

M

H

H

L

2
3

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61

Task #4
Some Preliminary Implications for
Resource Exploration

Introduction
to theProblem

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Identify
Resources on
Mars, Establish
Reference
Cases

Engineering
Analysis ofReference
Cases

Water ISRU Planning, April 2016

ExploreSensitivity ofEngineeringto Geology

Preliminary
Exploration
Implications

62

Overview of Mineral Exploration
Typical Earth-based exploration process andapplications to Mars ISRU
1.

Develop a concept: What commodity do you want to look for? Whatdeposit type(s) & appropriate geology? What is the politicalinfrastructure? Decide where to go and do basic reconnaissance inthose areas.
– For Mars: Looking for water and have identified four potential deposit types. Geographic
determination comes from the engineering requirement to stay <50° latitude (rather thanpolitical infrastructure). Existing missions are doing basic reconnaissance.

2.

Identify places worth a closer look, and stake claims or negotiate
leases. Do initial exploration such as soil samples, systematic rockchip samples, geophysical surveys, geological inference. Out of 1000
places where you do this, maybe 100 will look promising enough tostart doing expensive work.
– For Mars: This step will need to be done entirely from orbit, as only after a down-selectwould we be willing to send landed missions. Initial exploration would be high-resolution
orbital spectroscopy augmented by historical and structural implications of topography
and geophysics.

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63

Overview of Mineral Exploration
3.

Develop drill targets and test them, modeling the results and doing several
rounds of follow up. Do initial metallurgical work. Out of 100 prospects thatlooked good enough to drill, perhaps a dozen will look promising enough tocontinue to development work.
–

4.

Produce a detailed ore body model and begin engineering plans. Continue
metallurgical testing and begin baseline environmental monitoring. Produce
a Preliminary Economic Assessment. Of a dozen properties undergoing this,perhaps 3 or 4 will have a positive assessment and advance to the nextstage.
–

5.

For Mars: This will be done by robotic tools such as RASSOR. By working smart, could weshortcut the numbers of how many tests are required to find prospects worth advancing, or is it
possible that the uniqueness of location would over-ride the possibility of shortcuts?

For Mars: The equivalent of metallurgical testing might be determining the recovery rate of
potable or feedstock-quality water. The equivalent of Economic Assessment might be study ofenergy necessary. Can we work smarter here?

Perform final engineering and bankable feasibility studies. Open up the ore
body with a preliminary pit, decline, or shaft and begin bulk sampling andtest mining. One deposit from a thousand may survive to become profitable!
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64

Do Deposits as Good or Better than the
Reference Cases Exist on Mars?
• The analysis in Sections #2-3 of this report is based on the set of
hypothetical reference deposits described in Slide #17. The
question we have been asking to this point is if deposits at least
as good as these could be discovered and characterized, would
any of them be good enough to justify an ISRU operation?
• We do not know (yet) whether or not deposits of at least thisquality actually exist on Mars in a minable configuration and in alocation that is accessible to human explorers.
• We also have only partial information related to the consequenceof making a discovery that is significantly better or worse than
the reference cases.
• Some crucial exploration-related questions related to Slide #61:
– How could this knowledge be generated?
– How much risk associated with incomplete knowledge is acceptable?
– What is the most expeditious path to making the discovery needed?
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What Would it Take to Get to Reserves?
1. One implication of “reserves” (see Slides #10-11) is that the inplace raw material is known to be present (at a certain
confidence level) in the form that the extraction and processing
engineered systems can be reliably designed.
2. Although all of the knowledge specified on Slide #61 mattersfor establishing this confidence, on Earth we have learned fromexperience that:
1.
2.
3.

In cost-constrained exploration programs, it is common that not all of thedata desired can be afforded.
Some information related to exploration questions is more useful for
decision-making than other information.
Not all information related to exploration questions is equally expensive.

FINDING #5. In order to optimize an exploration program, it is very
important to prioritize information needs, costs, and decisional value.
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Information of Highest Priority to
Engineering
The information of highest priority to determining engineering
viability (Slide #61). Are these the parameters of greatest
usefulness in exploration screening?
CASE

#1

#2

#3

A1 (Ice+open pit)

Thickness ofoverburden

Mechanical properties ofoverburden

Mechanical consistencyof ore deposit

A2 (Ice+subsurface)

Mechanical consistencyof ore deposit

Thickness of overburden

Mechanical propertiesof overburden

B (hydrated sulfate)

2D geometry/size ofore deposit

Mechanical consistencyof ore deposit

Distance to processingplant

C (clay)

2D geometry/size ofore deposit

Mechanical consistencyof ore deposit

Distance to processingplant

D (regolith)

Water concentration ofore deposit

Mechanical consistencyof ore deposit

Chemical properties ofore deposit

Information in cells shaded in blue are those for which preliminary assessments can be madefrom orbit, those in green require data collected in situ. For Case A2 only parameter #1 was
ranked high priority, parameters #2 and #3 (in italics) were ranked medium priority.
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67

The Importance of Scale
•
•
•

•

•

An aspect of Slide #61 that needs more consideration is the minimum
required scale for each of the categories of knowledge described.
For all of these, the scale of our need to know is different in the verticaland horizontal dimensions—these need to be considered separately.
For horizontal scale, mining operations can be sensitive to variations(concentrations, rock properties) on the scale of centimeters.
Measurements at this scale cannot be done with passive spectral
imaging from orbit, and Opportunity and Curiosity have shown that it
can be hard to find minerals detected in CRISM footprints (bestresolution 18m/pxl) as they are sequestered in the fine structure of thesurface in high concentration but over limited areal extent.
The NEX-SAG report has pointed out that getting finer spatial resolution
coverage will help, but this would probably not be available at equally
good resolution everywhere on Mars.
For vertical scale, the capability of measurement from orbit is different
for the different cases, and the sensitivity of the mining operations would
be different for the different cases – depending highly on access.
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68

The Importance of
Subsurface Knowledge•••

For Case A, the depth to top of ice is perhaps the single most important pieceof information needed (see Slide #67). This could be generated to withinsome level of precision using an orbital SAR (see NEX-SAG, 2015).
For the mineral-based cases (B-C-D), we have the limitation that mostaqueous mineral detections are in the short-wave IR (e.g., OMEGA, CRISM)
looking at reflected sunlight, which probes only microns deep. This is equallytrue of orbital- vs. lander-mounted instruments. Estimates of the depth ofthese deposits below that can only be done using the principles of geologic
inference, and modeling how hydrated these deposits are at depth could be
supplemented by additional simulant testing or field work in similar deposits.
Determining whether the mechanical consistency of the material to be moved(overburden in Case A; ore in cases B-C-D) is within acceptable bounds ishard to measure directly. Some geological processes associated with thecreation/deposition of granular materials are associated with size sorting.
These processes need to be understood, and models developed for
how/when they were active on Mars. This can give us models for size
distribution that could have predictive value. Key remaining issues are thepriority and methods for testing these models.
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69

This is a 2-step (at least)
Exploration Problem
FINDING #6. Using orbital data alone it is not possible to collect thedata necessary to achieve “proven reserves” for any of Cases A-B-C.
Some of the required data are not observable at all from an orbiter,and others cannot be observed at an appropriate spatial scale.
•

The best we will be able to do from orbit is to identify places ofenhanced potential, or maybe “possible reserves” (see Slide #10).

FINDING #7. All of the parameters listed on Slide #61 can bemeasured from a properly-equipped rover, as long as it is sent to theright place.
•

There is a time factor that matters. When is the earliest that we
can get data from the second mission and when is it needed inorder to influence mission architecture?
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The Importance of Decisional Support
ORBITAL RECON

Which data sets would provide themost effective screening to define
discrete, evaluatable, prospects?

PRIORITIZED SET
OF PROSPECTS

Which data sets would be most usefulin prioritizing prospective landing sites
identified?

PROSPECTIVE LANDING
SITE(S) EXPLORED

How could we maximize the probability
that the prospective landing site(s) we
explore on the ground will be able tomeet remaining requirements?

Note: Creating a list of possible or proposed steps or missions to accomplish each step is
an important piece of follow-up work, captured in #20 on Slide #85.
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Exploration Risk (1 of 3)
What is the exploration risk (= the risk of failing to make an acceptable discovery)?
• We don’t know how rare, within the available geologic provinces, ore deposits
that meet/exceed minimum engineering specifications would be. The
exploration risk would depend on the engineering tolerances and the naturalgeologic variation. The rarer the occurrence, the harder the exploration problem.
• For all of our reference ore deposit cases, potential deposits will have adispersion about a mean, with some instances being better than average, andothers being worse than average.
Number of
Occurrences above
Minimum Required
for “Reserves”

highCase D

Deposits that are “rarer” (relative to the set of occurrencesthat actually exist) can be better, but harder to find/delineate.
Deposits that are “commoner” can be worse, but easier tofind.

Cases A-B-CGold on
Earth

low
low

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Degree of Selectivity (and Risk) in Exploration
Water ISRU Planning, April 2016

high
72

Exploration Risk (2 of 3):
Case D - Regolith••

We have data for the water content of
the regolith, at a scale relevant tomining, for ONE place on Mars: Gale
Crater (and this has been used todefine Case D; 1.5% WEH).
What is the risk that at somegeologically similar alternate site, thevalues are less than minimum
acceptable values? How can this risk
be estimated?
– Modeled values from DAN go as low as 1.02+/- 0.04% WEH (data from Sol 59)•

Would continued data collection from
DAN in addition to the data fromFREND (on ExoMars-TGO – spatial
resolution up to 30-40m) help tounderstand this risk?
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Unusually H-rich area of Mars’ surface detected by
DAN, showing data through Sol 1051 – note thatcolor coding is by passive count rate, and that thisis correlated to WEH by measuring the time after
PNG pulse – WEH is calculated from a model, andis not directly equivalent to hydration state (JPL
Press Release, August 19, 2015)

Water ISRU Planning, April 201673

Exploration Risk (3 of 3)
Cases
A-B-C

VERY HIGHRISKHIGH RISKMED RISK*

Case D

Number andDifficulty ofEngineering
Requirements(= Risk of Failing to Identify Necessary Reserves)

HIGH RISKMED RISK

L-M RISK?

Today’sdata+ oneorbiter+ orbiter+ lander*could belower if you
hit paydirt
with firstlanderQuantity/quality of Data Available
Assuming that reserves are present without sufficient exploration is a high-risk strategy. This risk
can be reduced by acquiring data (this is a classic problem in the exploration community on Earth.

FINDING #8. We can buy down risk by means of purchasing data.
However, the risk cannot be taken to zero (Q: how much residual risk
is acceptable?).
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When Would Investment Be Made?
Case A (Ice)higherCOSTS

Case B-C-D(Gypsum,Clay, Regolith)
not necessarily
the same scale

lower
early
(mostly exploration phase)

TIMINGlate(mostly engineering phase)

Comparison of the phasing of investments. Experience from Earth-based exploration-mining
projects is that early exploration-related investments pay off many-fold in later engineering
related investments.
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Water ISRU Planning, April 201675

An Alternative Risk-balancing Strategy
Since Case D (typical martian regolith) is postulated to be
applicable at almost any location on Mars, these ores
could be assumed to exist in conjunction with each of ourother deposit types (Type A, B or C). This allows for thefollowing variant that draws the astronauts into the
exploration process (after arrival):
Set up the initial engineering system sized so as to make use of
Case D (low grade deposits), but keep the option open of shiftinglater to Cases A, B or C (higher grade deposits) for the long term
once validated. This would also provide reserves if Cases A, B or C
could be found. Drawbacks: 1) Cannot know in advance if this isfeasible 2) Requires oversizing for worst case in several dimensions(greater # of excavators, larger throughput, higher processing
temperatures / power levels) 3) Processing has to be compatible.
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Some Timing Considerations, andLanding Site Selection• As discussed on Slide #70, it is impossible to achieve proven water
reserves, for any of the resource types considered, with one exploration
orbiter. At least one lander is also required.
• That lander would need a landing site. It would be highly advantageous if thatsite were the actual human landing site. However, if knowledge of provenwater reserves is a prerequisite to selecting the human landing site, it may
not be possible to choose the latter to within reasonable risk standards until
after an exploration lander mission has been completed.
• This suggests the following decisional logic:

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Robotic
Lander
Water ISRU Planning, April 2016

Final humanlanding site
selected

ProvenReserves
identified

Orbiter

Possible
Reserves
identified

Relationships involving
the timing of finalizing
the selection of ahuman landing site.

Provisional
human landingsite selected

Human
Mission to
Surface77Conclusions

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Water ISRU Planning, April 201678

Conclusions (1 of 2)
•

•

•

•

•

•

ISRU would significantly reduce the total overall mass which needs to be sent to Mars. The baseline
assumption would be that we are only producing LOX using atmospheric ISRU. However, for a relatively small
increase in the initial mass of ISRU equipment sent to Mars, CH4 could also be produced, dramaticallyincreasing propellant produced by a factor of 6 per kg of total ISRU system mass.
There is reasonable potential to produce mission-significant quantities water on Mars, using systems that may
be compatible with the architecture of a human mission, from at least 4 potential resource types (ice,polyhydrated sulfate concentrations, phyllosilicate concentrations, regolith).
Mining subsurface glacial ice by open pit methods would have multiple challenges. It would be particularly
sensitive to the thickness of the overburden, and to the mechanical properties of the ore. For all but theshallowest glacial ice deposits (2-6m), this approach would require processing larger amounts of material thansurface mining of hydrated minerals or typical martian regolith.
“Down-hole” or “In Situ Recovery” of subsurface glacial ice by sublimation/recondensation (Case A2) appears tobe the most promising approach to subsurface ice access but is the least mature technology. This study was
not capable of performing direct comparison with the other cases at this time.
Producing water from typical martian regolith would require both collecting the most “dirt” and the greatest
processing energy compared to other surface mining approaches, because the grade would be so low. For thisreason, it would be especially sensitive to transportation distance, and to heterogeneity in grade, but offers themore flexibility in terms of landing site options and still offers a favorable system mass trades.
A deposit of poly-hydrated sulfate (Case B) minerals appears to be the most advantageous reference case (notincluding the down-hole case). The viability would be particularly sensitive to the distance from the deposit tothe other infrastructure (e.g. power, extraction plant). This might be minimized by strategies that involve
specialized classes of rovers (excavators vs. transporters) and/or field processing of the ore into water/ice fortransport (subject to movable power/heat sources such as smaller movable reactors or RTGs). Surface granularmaterial excavation technologies are at relatively high TRLs.

Conclusions (2 of 2)
•

•
•
•
•

•

•

The phyllosilicate reference case (Case C) is significantly inferior to the polyhydrated sulfate case, andonly somewhat better than typical martian regolith. In order for this deposit type to be competitive, we
may need either a deposit of a mineral that has more water than smectite, and/or a higher smectite
concentration than in the reference case.
The establishment of “reserves” in any of the four cases evaluated in this study would require a).
Refinement of the production method, b). An exploration program.
We do not yet know whether deposits as good or better than the reference cases used in this study, andin a minable configuration, exist on Mars.
It is not possible to collect the data necessary to achieve “reserves” using orbital data alone. This is a 2step (at least) exploration problem, involving both an orbiter and a follow-up landed mission.
Due to the engineering importance of mineral deposit properties that are not measureable from orbit, asignificant portion of exploration risk could be reduced by a robotic surface mission sufficiently earlier
than the planned human landing that its findings could be incorporated in mining method/technology
design and development.
Several attributes of the natural geological variation of the deposits represented by the reference cases
have the potential to exert a significant influence on the basic viability of candidate sites, as well as theengineering architecture. Choosing and optimizing a specific engineering design is therefore dependent
on knowledge of these properties. The exploration missions should be designed to focus on acquiring
these data.
Two general factors that will be important in establishing “reserves” are scale and subsurface
knowledge. These need more discussion.
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Water ISRU Planning, April 201680

Some Identified Areas for
Follow-up Work (1 of 6)
This scoping analysis is intended to provided guidance regarding a number of complex and interrelated issues, and for which follow-up action by a number of different entities would be
beneficial.

General1.

2.

3.

We encourage broader community discussion of these water ISRU issues at open
conferences, such as the Space Resources Roundtable and the ASCE Earth and Space
Conference, especially those that support the publication of referenceable documents.
We encourage the continued development of engineering concepts and geological data forboth of the primary pathways identified: ice, and hydrated minerals. It is too early to attempt
to prune either of these two branches of the trade space.
a.
We currently have better data for the granular “regolith” and “mineral” cases (Cases BC-D) than the ice cases (A1 & A2), and we really need to improve our understandingof the latter to bring them to an equal level of detail and understanding.
The possible or proposed steps or missions to accomplish each stage along the decisional
support pathway should be identified, from orbital recon to prioritized set of prospects toprospective landing site(s) so that these missions can get appropriate emphasis.

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Some Identified Areas for
Follow-up Work (2 of 6)
Technology Development
4.

5.

6.

7.

Technology concepts should be matured for potentially competitive methods ofheating/subliming ice from depth with cold-trap recovery at the surface, or excavation
without a cold trap, through drill-holes that are less sensitive to depth of deposits than open
pit ice mining.
The trade between dedicated prospecting rovers, excavators, regolith processing on
vehicles, and/or regolith/product transport vehicles should be determined based on anumber of factors. (We may still want to have a common rover chassis/bus with different“specialized” attachments vs. completely different rover chassis.)
Given the lower temperature/energy requirements, systems such as a plutonium RTGpowered (~2 kW thermal, ~100-150 W electrical) “field retort” where ore could beprocessed into water at the mine location and only water/ice transported back to the fuelprocessing plant co-located with the MAV/reactors should be considered for optimization,in conjunction with “specialized” rovers for gypsum (and potentially smectite). Also, smaller,
modular portable fission reactors (10 kW or less) might be advantageous in this scenario.
Establish the feasible working lifetimes (processing cycles, haul trips, etc.) of potential
technologies (specialized or generic rovers, retorts, etc).

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Some Identified Areas for
Follow-up Work (3 of 6)
Advanced Mission Planning
8.

Continue refinement of engineering parameters for resource reference cases A, B, C, and D.
Continue working trade studies on distance and resource parameters with HAT ISRU team. Divemore into icy soil evaluation as a function of depth from 1 to 3 meters.
9.
Gain a better understanding of the effect of surface properties and terrain on mining method
concepts. Use this to identify better terrestrial ‘feedstock’ for creating simulants that represent
these 4 resource types for upcoming ISRU development activities.
10. Study the effects of over- and under-sized material on excavation forces, durability of equipment
and processing systems, and efficiency of excavation and processing methods. Develop mitigation
approaches.
11. Continue to examine the impact of the power architecture on mining method and hardware sizing.
12. Integrate mass/cost estimation approaches: Overall economics of these and other (subsurface ice)
will depend not only on mass / cost estimates for the systems described by this analysis, but also
estimates of the alternatives, such as:a. Mass / complexity of flight excavators, flight ore processing reactors, flight water  fuelprocessing systems.
b. Analysis of the development and launch/transportation costs (and reliability) and of how thesesystems trade against either:• directly transporting the required propellants from earth (without water processing) or• transporting water (or other hydrogen source) from earth for manufacturing propellant using
native carbon/CO2
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Some Identified Areas for
Follow-up Work (4 of 6)
Improved Understanding of Mars
13.

14.

15.

16.

17.

Assess the potential of various martian geologic provinces to contain deposits of categories
A, B, or C that meet or exceed the hypothetical driving specifications used in this analysis.
Are our hypotheticals overly rare (making the exploration problem too hard) or overly low
grade (making the engineering problem unnecessarily difficult)?
Analyze how effectively we can use the principles of geologic inference to model variation
with depth, since this cannot easily be directly measured. Can this be studied via Earthanalogs?
Identify local characteristics of deposits: How homogeneous are the deposits over different
scales (across surface, x-y, or in depth, z)? Presence of impurities or larger “rocks” in thedeposit that would reduce efficiency of either excavation or water extraction?
Gain better understanding of the concentration-frequency distribution of water in theregolith, including the on-going operation of the DAN instrument, and better understandingof the mineral phases that the water is stored in, including more measurements of regolithfrom the SAM instrument. This is a key input for estimating the risk that sites other thanGale Crater have lower values of water than Case D (regolith) and for bounding thevariability in similar locations.
Once exposed, the ice deposit would be unstable w.r.t. sublimation. We need a better
understanding of the rate of this process, including its practical significance to waterproduction methods and the need for mitigation strategies.

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Some Identified Areas for
Follow-up Work (5 of 6)
Refinement of Exploration Strategy
18.

19.
20.

21.

22.

Produce a better definition of the degree of confidence implied by the term “reserves” (forMars), and especially, more widespread agreement on risk tolerance (both probability andeffect) in this context.
Define the set of standards that a “reserve” feasibility study must meet for Mars waterproduction.
Have more discussion of the risks, and possible risk mitigation strategies, associated withdown-selecting to the landing site for a possible landed exploration mission. What are theessential data sets, and spectral and spatial resolution, needed to support this decision?
Slide #71 needs to be followed up with an analysis of the possible or proposed steps or
missions to accomplish each step.
Create a better analysis of which data sets would provide the most effective screening todefine discrete, evaluatable, prioritized, prospects.
a. Evaluate the potential value to the exploration flow of the FREND data set from TGO.
b. Evaluate the potential value to the exploration flow of the data that could be produced
from various candidate instruments on NASA’s NeMO mission.
Incorporate the principal conclusions of this analysis into the workshop series associatedwith identifying and prioritizing candidate human landing sites (HLS2).

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Some Identified Areas for
Follow-up Work (6 of 6)
Other
23. Have additional discussions of planetary protection concerns.

Note:• The concept of producing water on Mars would raise a number of questions if evaluatedagainst the Planetary Protection policy of 2016.
– Would any of the approaches to extracting ice create an ‘induced special region’?
– Would the establishment of reservoirs of water inside the various engineered systems
create microbial habitats that would be an issue?
• However, the key is the relationship of these ISRU issues to the future PP policy that would
be in place at the time the human missions happen—that policy has not yet been written.

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Appendix

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Water ISRU Planning, April 201687

Affiliations
M-WIP Committee Members
Name
Abbud-Madrid
Beaty
Boucher
BusseyDavis
GertschHays
Kleinhenz
Meyer
Moats
MuellerPaz
Suzukivan Susante
WhetselZbinden

Angel
Dave
Dale
Ben
Richard
LeslieLindsay
Julie
MichaelMichaelRob
Aaron
NantelPaulCharles
ElizabethAffiliation
Colorado School of Mines
Mars Program Office, Jet Propulsion Laboratory - California Institute of Technology
Deltion Innovations Ltd.
NASA - Headquarters
NASA - Headquarters
Missouri University of Science and Technology
Mars Program Office, Jet Propulsion Laboratory - California Institute of Technology
NASA - Glenn Research CenterNASA - Headquarters
Missouri University of Science and Technology
NASA - Kennedy Space CenterNASA - Johnson Space CenterNASA - Headquarters
Michigan Technological University
Mars Program Office, Jet Propulsion Laboratory - California Institute of Technology
Geological Society of Nevada

Reviewers
Name
HoffmanParrishSandersZurek
4/25/2016

StevenJosephGeraldRichardAffiliation
NASA - Johnson Space Center
Mars Program Office, Jet Propulsion Laboratory - California Institute of Technology
NASA - Johnson Space Center
Mars Program Office, Jet Propulsion Laboratory - California Institute of Technology
Water ISRU Planning, April 201688

Acronyms & Definitions
•
•
•
•
•
•
•

•
•
•
•
•
•

CheMin – Chemistry and Mineralogy Instrument (instrument on the2011 MSL rover)•
CRISM - Compact Reconnaissance Imaging Spectrometer for Mars •(instrument on the 2005 MRO orbiter)•
DAN – Dynamic Albedo of Neutrons (instrument on the 2011 MSL •rover)•DRA – Design Reference Architecture•
EDL – Entry, Descent and Landing•
EMC – Evolvable Mars Campaign•
FREND - Fine Resolution Epithermal Neutron Detector (instrument•on the 2016 ExoMars-TGO orbiter)
HAT – Human Architecture Team•
HLS2 – Human Landing Site Selection
ISRU – In Situ Resource Utilization•
LCH4 – Liquid Methane•
LOX – Liquid Oxygen•
MARSIS - Mars Advanced Radar for Subsurface and IonosphereSounding (instrument on the 2003 Mars Express orbiter)
MAV – Mars Ascent Vehicle
MRO – Mars Reconnaissance Orbiter
MSL – Mars Science Laboratory
NEX-SAG – Next Orbiter Science Analysis GroupPP – Planetary Protection
RASSOR – Regolith Advanced Surface Systems Operations Robot
ROI – Region of Interest
RSL – Recurring Slope Lineae
SAM – Sample Analysis at Mars (instrument on the 2011 MSL
rover)
SHARAD – Shallow Subsurface Radar (instrument on the 2005
MRO orbiter)
TGO – ExoMars Trace Gas Orbiter
TRL – Technology Readiness Level
WEH – Water Equivalent Hydrogen

Definitions (terms as used in the context of this study)• Exploration: As applied to resource deposits, the set of activities that result in the discovery anddelineation of reserves.
• Feedstock: The output of one industrial process that is input to another.
• Mining method: The spatial (layout) and temporal (scheduling) sequence of mining activities.
• Resource: (1) Any useful raw material (2) A natural concentration or enrichment of water-bearing
material that has the potential to become a proven reserve.
• Processing: Activities related to extracting, refining, and purifying the water from mined ore.
• Production: The combined activities of mining + processing for which the output is a commodity.
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References
•
•
•
•
•
•
•
•
•

•
•
•
•

•

Bussey, D.B.J. and S.J. Hoffman, Human Mars Landing Site and Impacts on Mars Surface Operations, 2016 IEEE Aerospace Conference, Big Sky MT, Mar
5-12, 2016.
Drake, B. G., ed., 2009a, Human Exploration of Mars Design Reference Architecture 5.0 (DRA 5.0), NASA Special Publication -2009-566, 100 p., Led by theMars Architecture Strategy Group: Beaty, D.W., Vicki Crisp, Bret Drake, Scott Goodwinn, George Tahu, Jeff Volosin; available electronically at
http://www.nasa.gov/pdf/373665main_NASA-SP-2009-566.pdf
Drake, B. G., ed., 2009b, Human Exploration of Mars Design Reference Architecture 5.0 (DRA 5.0) Addendum, NASA Special Publication -2009-566
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