clear over length scales greater than landing ellipse
• Resource Regions of Interest
• One or more potential near-surface (≤3m) water resource
feedstocks in a form that is minable by highly automated
systems, and located within ~1-3km of ISRU processing
and power infrastructure. Total extractable water should be
~100MT (supports ~5 missions)
• Show potential for minable metal/silicon resources, mainly
Fe, Al, and Si, located within ~1-2m of the surface
• Science Regions of Interest
• That address MEPAG goals (i.e. Astrobiology, Atmospheric
Science, and Geoscience)
Exploration Zone (EZ) – Current Definition
April 16th 2020 3Pre-Decisional Information -- For Planning and Discussion Purposes Only
Concept Drawing
Concept Drawing
Concept Drawing
Mars Water Mapping Projects
April 16th 2020 Pre-Decisional Information -- For Planning and Discussion Purposes Only 4
Subsurface Water Ice Mapping (SWIM) Hydrated Minerals Mapping
Putzig & Morgan et al. (PSI)
Team
1
Carter et al. (Paris-Saclay Univ.)A Global Aqueous Mineral Abundance Catalog for Mars
Team
2
Seelos et al. (APL)CRISM-Derived Global Map of Hydrated Mineral Bearing Units
Global Map of Areal Extent of Hydrated
Mineral Detections [Carter et al.]
Map of two types of hydrated
minerals and bound water over
the Mars 2020 Nili Site
Candidates [Seelos et al.]
Northern Hemisphere Ice Consistency Map
Northern Hemisphere Map of Base
of Deep Subsurface Ice Layers
Ongoing projects to create the best possible maps of water distribution by combining currently available orbiter data
Mars Water Mapping Projects
April 16th 2020 Pre-Decisional Information -- For Planning and Discussion Purposes Only 5
Subsurface Water Ice Mapping (SWIM) Hydrated Minerals Mapping
Putzig & Morgan et al. (PSI)
Team
1
Carter et al. (Paris-Saclay Univ.)A Global Aqueous Mineral Abundance Catalog for Mars
Team
2
Seelos et al. (APL)CRISM-Derived Global Map of Hydrated Mineral Bearing Units
Global Map of Areal Extent of Hydrated
Mineral Detections [Carter et al.]
Map of two types of hydrated
minerals and bound water over
the Mars 2020 Nili Site
Candidates [Seelos et al.]
Northern Hemisphere Ice Consistency Map
Northern Hemisphere Map of Base
of Deep Subsurface Ice Layers
Ongoing projects to create the best possible maps of water distribution by combining currently available orbiter data
MOCCAS
A Mars Orbital Catalog of Chemical Alteration Signatures
Mapping water minerals
Institut d’Astrophysique Spatiale, Paris-Saclay University, FranceTeam: J. Carter, F. Poulet, L. Riu, G. Alemanno
Remote sensing of Mars mineralogy
Aqueous mineraldeposit
Solar radiation interacts with water in Mars minerals
Remote sensing of Mars mineralogy
Aqueous mineraldeposit
Imaging spectrometersOMEGA (Mars Express - ESA)
CRISM (MRO – NASA)
Mars orbit spectra
Solar radiation interacts with water in Mars minerals
We detect thisfrom orbit
Near InfraredNear Infrared
Remote sensing of Mars mineralogy
Aqueous mineraldeposit
Solar radiation interacts with water in Mars minerals
We detect thisfrom orbit
Mars orbit spectra Earth mineral spectraImaging spectrometers
OMEGA (Mars Express - ESA) CRISM (MRO – NASA)
What orbital near-infrared spectroscopy can tell us
• Identify and map out tens of types of aqueous minerals
Clay and clay-likeSulfate saltsCarbonate saltsHydrated silica
Commonly:Example 10x10 km mineral map
• Identify and map out tens of types of aqueous minerals
Clay and clay-likeSulfate saltsCarbonate salts Hydrated silica
• Provides the major chemical makeup (iron, aluminum, magnesium etc.)
• Qualitative indication on how water is bound to the mineral, as H2O molecules or as hydroxyl (OH-)
Commonly:
We can do this on the 10s to 100s of meters scale, globally
Example 10x10 km mineral map
What orbital near-infrared spectroscopy can tell us
• A ten-year endeavor to map all types of aqueous minerals, globally at Mars
• We implement a sequential approach:
Find aqueous minerals deposits
Characterize their nature
Quantify their mineral abundance
Derive their water abundance
The MOCCAS Project
« abundance » refers to volume% or weight% within a « skin » located in the top <1 mm of the surface It is not a bulk volume abundance of the entire deposit Currently limited to clays and oxides: sulfate salt abundances are not derived yet
Limitations (1 of 2)
• Only a few mm of mantling by dust or ice can obscure signatures• Most aqueous minerals formed early, so 3+ Gyrs of geologic processes have obscured the deposits
Not accessible
Obscured by:- Dust- Ice/frost (H2O and CO2)-Young capping
Ancient surface visible
Only a fraction (<50%) of the ancient surface is accessible to remote sensing:
Limitations (2 of 2)
• We cannot readily infer the rock type in which the mineral of interest is detected
Example: same mineral (clay), two rock types
Left: dry mud (brittle) Right: mudstone (hard)
This is foreseen to impact resource availability & extraction cost
Limitations (2 of 2)
• We cannot readily infer the rock type in which the mineral of interest is detected
Not accessible
How thick ?
• No active means to probe thickness and get a mineral deposit volume
• Thickness estimates rely on high resolution topographic data and rare erosional windows
• Even retrieving the surficial abundance of a mineral in a rock is not trivial, we rely on complex models and laboratory measurements (see later slides)
How much?
Difficult to quantify how much of a mineral (or water) is present
Example: same mineral (clay), two rock types
Left: dry mud (brittle) Right: mudstone (hard)
This is foreseen to impact resource availability & extraction cost
• A ten-year endavour to map all types of aqueous minerals, globally at Mars
• We implement a sequential approach:
Find aqueous minerals deposits
Characterize their nature
Quantify theirmineral abundance
Derive theirwater abundance
Aqueous minerals, composition is color-coded
The MOCCAS Project
At each step, we procude maps at high resolution (200 m/pixel or better)
Landing ellipse
Global scale mapping
Landing ellipse
Local scale mappingJezero crater landing site for Mars 2020
The MOCCAS Project
The MOCCAS Project: 5-step method
1. Tune in to specific mineral absorption bands in the infrared using 2 instruments: OMEGA & CRISM
2. A scouting algorithm looks for most probable mineral signatures, globally at Mars
3. Systematic human supervision: we verify each candidate mineral deposit, globally: so there are no false positives & a high detection sensitivity. The most reliable approach.
4. Perform radiative transfer modelling (Shkuratov theory) on largest mineral deposits to derive the modal abundances of the rocks, except for sulfate salts (for now). Calibrate … validate … repeat !
5. Deduce from these modal abundances the major chemical elements (including H2O)
Clay deposits
Water : 4.3 wt%
Spectra extraction and spectral modelling
Modal abundances Water contentIdentification and mapping
Anhydrousminerals
Mars surface spectrum (CRISM)
Spectral model
Aqueous minerals:
From 2006-2011: pioneering work produced the first global inventory of aqueous minerals
• Roughly 1000 « sites » with aqueous mineral deposits identified• No detailed maps were built: limited knowledge of their spatial extent & composition
10 years of mapping with the MOCCAS project:From 1000s to 100,000s of aqueous mineral
deposits are now found, and analyzed
Results from MOCCAS – Aqueous mineralogy
Nili Fossae
GaleMeridiani
MawrthVallis
OxiaPlanum
Marineris
Results from MOCCAS – Aqueous mineralogy
DOMINANT MINERAL CLASSES:A more perceptible mapping approach:
Areas on Mars where aqueous minerals are found within a 10x10 km region (size of a landing ellipse)
Nili Fossae
GaleMeridiani
MawrthVallis
OxiaPlanum
Marineris
Results from MOCCAS – Aqueous mineralogy
DOMINANT MINERAL CLASSES:
Wherever we have access to the ancient surface, it is altered
The first map of water and chemical elements stored in aqueous minerals. Uses OMEGA/MEx @1km scale.
Results from MOCCAS – Abundances
> 0% > 10%
Surficial abundance of water in minerals (as OH or H2O) weight%
Water in sulfate salts (as H2O)Not quantified yet
Results from MOCCAS – Abundances
Nontronite clay Water in mineralsMawrth Vallis
candidate landing site
> 0% 50% > 0% 13%Weight% Weight%
2.5% 14%
• There is an additional, independent fingerprint for water in the spectral datasets• It is sensitive to water molecules adsorbed or more tightly bound (including in aqueous minerals)• It is not from ice or water clouds
• An average 4wt% water at low latitude throughout, regardless of the distribution of aqueous minerals. • The mode of binding is unclear. It may be more superficial than aqueous mineral deposits.
An additional reservoir of water at the surface ?
Other bound water in the surface regolith, weight%
Audouard+14
Aqueous mineral ressources and landing site constraints
Mantled +/- 40° Lat Alt < 1 km
Aqueous mineral ressources and landing site constraints
Mantled +/- 40° Lat Alt < 1 km Alt < 0 km
Prospect: 1. on deriving abundances (modelling)
Average relative abundance of aqueous minerals in deposits
Clay mineralsHydrated silica Sulfate saltsCarbonate salts Iron hydroxides
Relative water + hydroxyl content of aqueous minerals
< 1% 10s %
Hydrated silica
<30 %
Clay minerals
10-20 %
Iron hydroxides
5 %
Sulfate salts
20-50 %
Carbonate salts
< 1%
1. Additional laboratory measurements are required to infer abundances of sulfate salts. Task: Acquire optical constants using an infrared polarization bench or related setup
2. Additional calibration measurements to better constrain model errors. Total uncertainty is currently estimated to ±12.3 vol% for aqueous minerals.Task: making known mineral mixtures in lab, acquire spectra and compare to abundance modelTask: compare spectral signatures with the other form of bound water from Audouard+14
Expected result: provide ISRU ranking, globally or for a region of interest, which combines the following:
To be coupled with:
Prospect: 2. Abundance mapping from the km scale to the 100s m scale using CRISM
Task: Upgrade abundance mapping from OMEGA to include entire CRISM detection dataset
Expected result: Generate local scale abundance maps at 10-100 m/pix, for landing sites selection purposes
Jezero Delta (Mars 2020)
Prospect: 3. Attempt retrieval of the rock texture
• Orbital data from thermal inertia (OMEGA/Mars Express & TES/MGS) • Laboratory spectro-photometric study of rock texture in the infrared
Expected result: Provide additional insight on suitability of aqueous deposits for resource extraction depending on rock type (hardness, thickness)
