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NOTE ADDED BY JPL WEBMASTER: This content has not
been approved or adopted by NASA, JPL, or the California
Institute of Technology. This document is being made available
for information purposes only, and any views and opinions
expressed herein do not necessarily state or reflect those of
NASA, JPL, or the California Institute of Technology
.
Martian Moons eXploration (MMX) Japanese next-generation sample return mission
37TH MEPAG (2019)
• Launch in 2024 (TBD)
• Phobos: remote sensing & in situ observation
• Deimos: remote sensing observation (multi-flyby)
• Retrieve samples (>10 g) from Phobos & return to Earth in 2029 (TBD)
THE 1ST SAMPLE RETURN MISSION FROM THE MARTIAN SATELLITES!
WHY PHOBOS AND DEIMOS?
Regolith of Phobos/Deimos contains Martian building blocks, impactors, late accreted volatiles, ancient Martian surface components etc…
• Constrain the initial condition of the Mars-moon system
• Gain vital insight and information on the source(s) and delivery process of water (& organics) into Mars and the inner rocky planets
37TH MEPAG (2019)
MMX Science Goals
37th MEPAG (2019)
<Goal 1> To reveal the origin of the Martian moons, and then to make a progress in our
understanding of planetary system formation and of primordial material transport around
the border between the inner- and the outer-part of the early solar system
<Goal 2> To observe processes that have impacts on the evolution of the Mars system from
the new vantage point and to advance our understanding of Mars surface environment
transition
5
Mission Profile
Outward
Phobos Proximity
Return
Sun
Launch
Mars Arrival
Mars orbit
S/C Trajectory
Earth orbit
Mars Departure
2.5 hour (TBD) Stay
<Proximity Phase> <Landing>
QSO
Descent Trajectory
<Mission Profile>
Ascent Trajectory
Sep., 2024
Aug., 2025
Aug., 2028
July, 2029
(written above is an example, and could change in the future)
• The total of 5 years trip by use of chemical propulsion system• Interplanetary flight: 1 year for outward/homeward• Stay at curcum-Mars orbits 3 years
• Launch in 2024 • Phobos: landing• Deimos: multi-flyby• Return to Earth in 2029
37th
MEPAG
(2019)
6
Spacecraft Configuration
Launch Configuration
On-Orbit Configuration
Exploration Module
Return ModulePropulsion Module
As a result of Phase-A study, spacecraft system’s configuration and major specification are defined preliminarily.
Launch Mass : 4000kgThree stages system.Return module: 1780kgExploration module: 330kgPropulsion module: 1890kg
Mission Duration : 5 years
Sample Return Capsule
Sampler
(written above is an example, and could change in the future)
Science Instruments
500N-class OME
Landing Gear
High Gain Antenna
Propulsion Module
Return Module
Exploration Module
37th
MEPAG
(2019)
Nominal Science Payload
Payload Measurements
Wide-angle multiband camera (OROCHI)
• Global mapping of hydrated minerals, organics, and the spectral heterogeneity ofthe Martian moons
• Characterize the material distribution around the sampling sites
Telescopic camera (TENGOO) • Determine the global topography and surface structure of the Martian moons• Characterize the topography around the sampling sites
Gamma-ray, neutron spectrometer (MEGANE) (provided by NASA)
• Determine the elemental abundance beneath the surface of the Martian satellites(Provided by NASA)
Near-infrared spectrometer (MacrOmega) (provided by CNES)
• Global mapping of minerals, molecular H2O and organics of the Martian moons.• Characterize the material distribution around the sampling sites• Monitor the transport of H2O vapor, H2O/CO2clouds, and dust in the Mars
atmosphere (Provided by CNES)
Light detection and ranging (LIDAR) • Determine the Phobos shape and topography
Circum-martian dust monitor (CMDM)
• Detect and monitor: 1) the circum-Martian dust ring; 2) interplanetary dust; 3)Interstellar dust
Mass spectrum analyser (MSA) • Determine the mass and energy of ions from Phobos, Mars and Sun
Rover’s payloads (by CNES/DLR): Raman, radiometer, cameras
• Determine surface composition and physical properties
37TH MEPAG (2019)
ORIGIN OF PHOBOS AND DEIMOS
Two competing hypotheses are proposed for their origins
Capture of asteroid
Consistent with D- or T-type IR spectra
in situ formation by an impact
Consistent with low eccentricity & inclination
Image courtesy (Hiro Kurokawa)Image courtesy (Hiro Kurokawa)
37TH MEPAG (2019)
ORIGIN OF PHOBOS AND DEIMOS
D- or T-type spectrum is consistent with the capture origin
Blue: Phobos
If Phobos & Deimos are “giant impact origin”,
the spectra reflect either
• impact-related “dark” glassy debris, or
• thin surface veneer of regolith, or
• result of space weathering
Fraeman et al. (2012)
will be tested by MMX• gamma-ray & neutron, sample analysis
37TH MEPAG (2019)
• Low eccentricity (Jacobson & Lainey, 2014)
• Phobos: 0.001511, Deimos: 0.00027
• Low inclination (Jacobson & Lainey, 2014)
• Phobos: 1.076 deg, Deimos: 1.789 deg
ORIGIN OF PHOBOS AND DEIMOS
Low eccentricity and low inclination suggest the impact origin
If Phobos & Deimos are “capture origin”...
“Gold mine” for astrophysicists! New dynamical model to reconcile
37TH MEPAG (2019)
Visible & Near-infrared spectroscopyMacrOmega from IAS, France
• Spectrum range: 0.9-3.6 μm cf. OH = ~2.7 mm, H2O-ice = ~3-3.2 mm, organics = 3.3-3.5 mm
• Spatial resolution: 8.2 m/pix @ 20 km
Gamma-ray & Neutron spectroscopyMEGANE from APL, USA
• Elements: Mg, Fe, O, Si, Na, K, Ca, Th, U, H, C,
and Cl
• Penetration depth: up to ~1 m
REMOTE SENSING OBSERVATIONS
Distribution of “blue” and “red” units on Phobos (by MRO)~
10
km
Fe/Si/O differentiates achondritic (giant impact) and
chondritic (capture) compositions
37TH MEPAG (2019)
SAMPLE ANALYSIS: EXPECTED CHARACTERISTICS
Captured asteroid Giant impact
Petrology,
mineralogy
Unequilibrated mixture
of minerals, Hydrated
phases, Organic matter
Glassy/igneous texture,
High-T phases
Bulk chemistry Chondritic, Volatile-rich Volatile-poor
IsotopesPrimitive solar-system
signature
Mixed feature between
Mars and impactor
Oxygen and Cr isotopic compositions
Mars
Earth
achondrite
O-chondrite
CI
CR
CM
CV
CO
CV
CK
CO
Non-carbonaceous
Carbonaceous
Data compilation (R. Fukai)
37TH MEPAG (2019)
Coordinated in-situ and bulk analyses will provide constraints on the origin(s) of the returned samples
CONCLUSIONS
• The MMX spacecraft is scheduled to be launched in 2024, and return >10 g of Phobos
regolith back to Earth in 2029 (TBD)
• The origin(s) of Phobos and Deimos has been in debate: captured asteroid or in situ
formation by impact
• MMX will provide clues to their origins and offer an opportunity to directly explore the
building blocks, juvenile crust/mantle components, and late accreted volatiles of Mars
MMX will constrain the initial condition of the Mars-moon system,
and shed light on the source, timing and delivery process of water (& organics) into
the inner rocky planets
37TH MEPAG (2019)
SLIDES FOR QUESTIONS
MARTIAN SAMPLES ON PHOBOS?
Mars impact ejecta could exist in the regolith of Phobos
Numerical simulation (Ramsley & Head, 2013)
Mars ejecta on Phobos is expected to• experience much lower launch velocity
than Martian meteorites
⇒ preserve original information?
• contain a variety of ancient sedimentary
materials (with organics??)
⇒ cf. Martian meteorite = igneous rocks
Spray of impact ejecta on the Phobos orbit
37TH MEPAG (2019)
Phobos regolith provides a wealth of information on the ancient surface environments of Mars
in lake-bed mudstone at Gale crater
TWO SYNERGISTIC SAMPLING SYSTEMS
37TH MEPAG (2019)
Coring & pneumatic sampling maximizes MMX sample science
Core samplerAccess to Phobos building blocks beneath the surface (>2 cm)
Pneumatic samplerSelective sampling of Phobos surface veneer(incl. Martian samples!)
Martian Moons eXploration (MMX) Japanese next-generation sample return mission
• Launch in 2024 (TBD)
• Phobos: remote sensing & in situ observation
• Deimos: remote sensing observation (multi-flyby)
• Retrieve samples (>10 g) from Phobos & return to Earth in 2029 (TBD)
THE 1ST SAMPLE RETURN MISSION FROM THE MARTIAN SATELLITES!
37TH MEPAG (2019)
WHY MARS & ITS SATELLITES?–Geophysical & Geochemical Constraints–
37TH MEPAG (2019)
Mars represents a planetary embryo accreted <10 Myr after SS birth
Walsh et al. (2011); Dauphas & Pourmand (2011)
Mas
s Ear
th
0.1
1.0
Mars
Results of dynamical simulation Accretion timescale inferred from 182Hf–182W systematics
Model depends on
Hf/W ratio of the mantle
WHY MARS & ITS SATELLITES?–Geophysical & Geochemical Constraints –
37TH MEPAG (2019)
Martian mantle differentiated early & did not experienced global mixing
Kruijer et al. (2017)
Timing of Mars differentiation Coupled εNd-εW isotopic systematics
preserve source heterogeneity
formed early in the MO
MO differentiation
occurred within the first 50
Myr
146 S
m-14
2 Nd
syst
em (
silic
ate
diffe
rent
iatio
n)
182Hf-182W system (metal-silicate differentiation)
SATELLITES ARE MADE OF MARTIAN JUVENILE CRUST & MANTLE?
37TH MEPAG (2019)
Contains >35% of Martian materials; most come from the mantle!
Results of high-res. SPH simulation (Hyodo, Genda+, 2017)
Disk mass fraction vs. impact angle
Impactor
Martian
Cumulative fraction of disk particles and their original depth from the surface of Mars
>4RMars
cf. typical crust thickness = 30-60 km
WHY MARS & ITS SATELLITES?–Geological & Geochemical Constraints–
Martian surface records the historical evolution of environments
37TH MEPAG (2019)
Global distribution of aqueous minerals (Ehlmann & Edwards, 2014)
4 Ga 2 Ga Present
claycarbonate
sulfate/anhydrous
surface water
?
1
0oce
an
de
pth
[km
]a
lte
ratio
nm
ine
rals
H2O
H, H2
H2O
2, O
3
to space
to surface
Relationship btw water volume & aq. alteration minerals
WHY PHOBOS AND DEIMOS?
Regolith of Phobos/Deimos contains Martian building blocks, impactors, late accreted volatiles, ancient Martian surface components etc…
• Constrain the initial condition of the Mars-moon system
• Gain vital insight and information on the source(s) and delivery process of water (& organics) into Mars and the inner rocky planets
37TH MEPAG (2019)
MMX Science Goals
Goal 1:
• To reveal the origin of the Mars’ moons, and then to make a progress in our understanding of planetary system formation and of primordial material transport around the border between the inner-and the outer parts of the early solar system.
Goal 2:
• To observe processes that have impacts on the evolution of the Mars system, from the new vantage point and to advance our understanding of Mars surface environmental transition.
37TH MEPAG (2019)
MMX Science Objectives
Goal 1: (origin, formation, transport)
1.1 To determine whether the origin of Phobos is captured asteroid or giant impact.
1.2a (In the case of captured asteroid origin) To understand the primordial material delivery process (composition, migiration history, etc.) to the rocky planet region and to constrain the initial condition of the Mars surface environment evolution.
1.2b (In the case of giant impact origin) To understand the satellite formation via giant impact and to evaluate the how the initial evolution of the Mars environment was affected by the moon forming event
1.3 To constrain the origin of Deimos
Goal 2: (evolution)
2.1 To obtain a basic picture of surface processes of the airless small body on the orbit around Mars
2.2 To gain new insight on Mars surface environment evolution
2.3 To better understand behavior of the Mars air-ground system and the water-cycle dynamics
37TH MEPAG (2019)
37TH MEPAG (2019)
DeMeo & Carry (2014)
SIGNIFICANCE OF MMX
MMX will constrain more than the satellite origin
Giant impact
Asteroid capture
• Juvenile crust & mantle
• Internal structure
Historical migration of solar system bodies
• Material distribution/migration
• Asteroidal variation
(S. Tachibana)
SAMPLE ANALYSIS: EXPECTED CHARACTERISTICS
Captured asteroid Giant impact
Petrology,
mineralogy
Unequilibrated mixture of
minerals, Hydrated
phases, Organic matter
Glassy/igneous texture,
High-T & -P phases
Bulk chemistry Chondritic, Volatile-rich Volatile-poor
IsotopesPrimitive solar-system
signature
Mixed feature between
Mars and impactor Taylor (2010)
by remote sensing, in situ & sample analysis
37TH MEPAG (2019)
Captured asteroid Giant impact
Petrology,
mineralogy
Unequilibrated mixture of
minerals, Hydrated
phases, Organic matter
Glassy/igneous texture,
High-T phases
Bulk chemistry Chondritic, Volatile-rich Volatile-poor
IsotopesPrimitive solar-system
signature
Mixed feature between
Mars and impactor
SAMPLE ANALYSIS: EXPECTED CHARACTERISTICS
Peplowski et al. (2011)
Compositions of terrestrial planets and the Moon
Mars
by remote sensing, in situ & sample analysis
Po
tass
ium
(p
pm
)Thorium (ppm)
(S. Tachibana)
37TH MEPAG (2019)
FLOW CHART FOR DETERMINING THE ORIGIN OF PHOBOS
Origin of returned sample
Asteroidal origin
Mixture of
Asteroidal/Martian
Martian origin
Origin of Phobos
Yes
No
Capture of asteroid
formed in the outer
solar system Martian sample: GI origin?e.g. old age, high-T, volatile-free
In situ formation by
a giant impact on
Mars
Check the representativeness of the returned sample
Check the representativeness of the returned sample
37TH MEPAG (2019)
MEGANE IDENTIFIES PHOBOS ORIGIN
Lawrence+ (2018)
37TH MEPAG (2019)
LIST OF “KEY” ANALYSIS FOR THE RETURNED SAMPLE
Method Data type sample amount Notes
SIMS O, H, (C, S, etc.) isotopes ~10 μm dia. in-situ, destructive but limited to meas.
spot
IRMS O (C, S, N) isotopes <1 mg Bulk, destructive
IRMS Ar-Ar age <0.01 mg Bulk, destructive
TIMS Rb-Sr age ~10 mg Bulk, destructive
SIMS Mn-Cr age ~10 μm dia. in-situ, destructive but limited to meas.
spot
PGA/NAA Bulk chemistry ~1 g Bulk, non-destructive
ICP-MS Bulk chemistry ~10 mg Bulk, destructive
EPMA/TEM/Raman Mineral chemistry,
crystallography
<3 μm dia. in-situ, non-destructive
XAFS Chemical speciation ~1-10 μm dia. in-situ, non-destructive
SQUID
spectroscopy
Magnetic field ~1 μm dia. in-situ, non-destructive
Coordinated in-situ and bulk analyses will provide constraints on the origin(s) of the returned samples
37TH MEPAG (2019)
Regolith Particle Size
37TH MEPAG (2019)
1 µm
Lower limit of radiation pressure theory
70 µm 250 µm 1 cm1-3 mm
Particle size
Typical Itokawa regolith
Typical lunar regolith
Micro-particle in Itokawa sample
likely range
most likely?
・ Phobos regolith will be larger than the lunar regolith, and smaller than Itokawa
regolith. It is expected to be 70–1000 µm.
・Most particles are around 300 µm due to the radiation pressure segregation?
Personal comm. (K. Ogawa)
MMX Science Goals
37th MEPAG (2019)
<Goal 1> To reveal the origin of the Martian moons, and then to make a progress in our
understanding of planetary system formation and of primordial material transport around
the border between the inner- and the outer-part of the early solar system
<Goal 2> To observe processes that have impacts on the evolution of the Mars system from
the new vantage point and to advance our understanding of Mars surface environment
transition
International Collaboration
ESA
• JAXA and ESA are going to make a official agreement on MMX
• Ka-band communication equipment
• Ground station for data downlink
• Scientific involvement
NASA
• JAXA and NASA exchanged Letter of Agreement on MMX
• NASA issued an AO that solicits proposal for Gamma-ray and Neutron Spectrometer and selected MEGANE of JHU/APL
• Other items (DSN support, test facilities usage, etc.) are under discussion
37TH MEPAG (2019)
International Collaboration, cont.
CNES• JAXA and CNES made Implementing Arrangement on MMX
• Near-infrared Spectrometer (MacrOmega)• Flight dynamics• Feasibility of the small lander/rover to be equipped (w/DLR)
DLR• Collaboration items are under the discussion
• Experiments using the Bremen Drop Tower• Experiments using German facilities for landing mobility• Study and development of robotic arms• Feasibility of the small lander/rover to be equipped (w/ CNES)
37TH MEPAG (2019)
(S. Tachibana)
SAMPLE ANALYSIS: EXPECTED CHARACTERISTICS
Captured asteroid Giant impact
Petrology,
mineralogy
Unequilibrated mixture of
minerals, Hydrated
phases, Organic matter
Glassy/igneous texture,
High-T & -P phases
Bulk chemistry Chondritic, Volatile-rich Volatile-poor
IsotopesPrimitive solar-system
signature
Mixed feature between Mars and
impactor Taylor (2010)
by remote sensing, in situ & sample analysis
37TH MEPAG (2019)
Captured asteroid Giant impact
Petrology,
mineralogy
Unequilibrated mixture of
minerals, Hydrated
phases, Organic matter
Glassy/igneous texture,
High-T phases
Bulk chemistry Chondritic, Volatile-rich Volatile-poor
IsotopesPrimitive solar-system
signature
Mixed feature between Mars and
impactor
SAMPLE ANALYSIS: EXPECTED CHARACTERISTICS
Peplowski et al. (2011)
Compositions of terrestrial planets and the Moon
Mars
by remote sensing, in situ & sample analysis
Po
tass
ium
(p
pm
)Thorium (ppm)
(S. Tachibana)
37TH MEPAG (2019)
FLOW CHART FOR DETERMINING THE ORIGIN OF PHOBOS
Origin of returned sample
Asteroidal origin
Mixture of
Asteroidal/Martian
Martian origin
Origin of Phobos
Yes
No
Capture of asteroid
formed in the outer
solar system Martian sample: GI origin?e.g. old age, high-T, volatile-free
In situ formation by
a giant impact on
Mars
Check the representativeness of the returned sample
Check the representativeness of the returned sample
37TH MEPAG (2019)
MEGANE IDENTIFIES PHOBOS ORIGIN
Lawrence+ (2018)
37TH MEPAG (2019)
Regolith Particle Size
1 µm
Lower limit of radiation pressure theory
70 µm 250 µm 1 cm1-3 mm
Particle size
Typical Itokawa regolith
Typical lunar regolith
Micro-particle in Itokawa sample
likely range
most likely?
・ Phobos regolith will be larger than the lunar regolith, and smaller than Itokawa
regolith. It is expected to be 70–1000 µm.
・Most particles are around 300 µm due to the radiation pressure segregation?
Personal comm. (K. Ogawa)
37TH MEPAG (2019)
SAMPLE ANALYSIS: FLOW CHART
• ~1,000 grains for initial screeningFYI: ~1,000 grains = ~1 g (for ~0.3 mm size grain)
• ~100 grains for detailed petrology, mineralogy, in situ isotope analyses
• ~10 to 20 grains for bulk isotope analyses
~1 g for the MMX team
>9 g for the int. community!
37TH MEPAG (2019)
LIST OF “KEY” ANALYSIS FOR THE RETURNED SAMPLE
Method Data type sample amount Notes
SIMS O, H, (C, S, etc.) isotopes ~10 μm dia. in-situ, destructive but limited to meas.
spot
IRMS O (C, S, N) isotopes <1 mg Bulk, destructive
TIMS, ICP-MS Cr, Ti isotope <10 mg Bulk, destructive
TIMS, ICP-MS Rb-Sr, Sm-Nd, Pb-Pb age ~10 mg Bulk, destructive
SIMS Mn-Cr age ~10 μm dia. in-situ, destructive but limited to meas.
spot
IRMS Ar-Ar age <0.01 mg Bulk, destructive
PGA/NAA Bulk chemistry ~1 g Bulk, non-destructive
ICP-MS Bulk chemistry ~10 mg Bulk, destructive
EPMA/TEM/Raman Mineral chemistry,
crystallography
<3 μm dia. in-situ, non-destructive
XAFS Chemical speciation ~1-10 μm dia. in-situ, non-destructive
SQUID
spectroscopy
Magnetic field ~1 μm dia. in-situ, non-destructive
Coordinated in-situ and bulk analyses will provide constraints on the origin(s) of the returned samples
Formation age of the moon (or asteroid)
Age distribution of impacts
Regolith physical properties
37TH MEPAG (2019)
Origin of the moon
42
MMX-RoverP. Michel, S. Ulamec
Actual Rover design and Payload:
• Overall Rover with 29,1 kg including margin and 4 Payloads:• Raman Spectrometer, RAX (PI: Ute Böttger, DLR)• Radiometer, miniRAD (PI: Matthias Grott, DLR)• NavCAM (PI: Pierre Vernazza, LAM)• WheelCAM (PI: Naomi Murdoch, ISAE-SUPAERO)
• Optional Payload, considered during phase B:• Gravimeter, GRASSE (PI: Ö. Karatekin)• GPR, GRAMM (PI: D. Plettemeier)
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