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. MELOS: Japan’s Mars Exploration Plan for 2020’s

T. Satoh (JAXA) and MELOS Working Group

MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011) Science Target of MELOS z Understanding the Martian System z Interior + surface + atmosphere + surrounding space − To understand the evolution and to answer the fundamental question “Why (and how) is Mars different from the Earth?”, missions designed to study inter-relations between these are needed. − Both “orbiting” science and “landing” science are important.

Atmospheric escape to Degassing from the the interplanetary interior of the Keyword: space planet Why is Mars “red”?

Capture of the atmosphere to the Orbiter (A): Meteorology interior of the planet Orbiter (B): Aeronomy for MELOS-1

Lander (A): Surface Lander (B): Biology Transportation of Lander (C): Interior atmosphere and dust by meteorological Lander (D): Sample Return activities for MELOS-1 EDL and for MELOS-2 MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011) Orbiter (A): Martian Meteorology z Comparative Meteorology (Earth vs Venus vs Mars) − Similarity: rotation period, tilt of the pole

zTenuous CO2 atmosphere vs suspended dust (heat source) zLarge seasonal variation (eccentricity) vs relatively small thermal inertia zEpisodic “global” dust storm zUnderground water (ice) reservoir z Transportation/Relocation of Water & Dust − Never been studied in detail zLimitation of “local-time fixed” orbit zNeed to characterize “global” transportation zEspecially in the lower-most atmosphere z3-D structure of temperature, composition, isotopic ratio, etc.

MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011) Lander (B): Astrobiology z Most likey place for Martian life? − Surface soil near the methane vent zTerrestial life may survive at a few cm below Martian surface. zMartian environment ~4 Gy ago similar to Earth. zThe birth of life can be in very short time. zMartian methane detected recently. zBacteria that utilize methane & iron oxide discovered. z Method? − With fluorochrome and a microscope zDye protein, membrane, catalyst, etc. zTarget sensitivity: 10 cells / 1 g of soil. (compared to 104 cells / 1 g in Earth desert) zConclude “no life on Mars” if no detection. zPossibly detect organic materials related to chemical evolution before life.

Antarctic soil after dying MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011) Lander (C): Interior Structure (Depth) Preliminary Reference Interior Structure Model on Mars (PRISM2) Heat flow Electromagnetic (>2 stations)

Rotation Mars-quake (better to have multiple stations) (better achievement with multiple stations) (precession, nutation) (quakes, free oscillations) Z Term of Mars Possible collaboration with International network mission (Information) MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011) Selecting from Proposals to MELOS1

− The selection process: zReview & evaluation through hearings (the 1st one will be in August) zWill evaluate scientific significance, feasibility (TRL, resources), lander-orbiter synergy, etc. zOne of orbiter proposals will be selected first zWill keep 2 possible candidates for EDL science until later phase

MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011) International Challenges to Mars z Launches in all possible windows − Sample return in late 2020’s zNASA+ESA2016, 18 z2011: Curiosity (MSL) (USA) z2013: MAVEN (USA) z2011: Phobos-Grunt (Russia) + YH-1 (China) zIndian Mars mission (2018?) z Japan: NOZOMI (launch in 1998) − Failure before arrival at Mars zThen, we had HAYABUSA, KAGUYA, and AKATSUKI z2014: BepiColombo Mercury mission with ESA zSPRINT-A/EXCEED (Earth-orbiting EUV telescope) zPlans of lunar, asteroidal, planetary missions zWe challenge Mars, the planet like the Earth, with MELOS!

MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011) What's happend to “Akatsuki” Venus Mission z VOI attempted on 7 Dec 2010 but failed... z Likely cause is “clogged” check valve in the fuel line (CV-F) − It prevented smooth flow of fuel, resulting in “less fuel than oxidizer” condition (O/F > 1). − The excess fuel acts as “coolant” for the thruster throat & nozzle. This does not work if the fuel is less than the oxidizer. − Without enough cooling, a damage has occured to the thruster, and the spacecraft went to “Safe Hold”. – The spacecraft (including mission instruments) seems to be in good condition, and we will re-challenge VOI 6 years later.

MELOS Mars Exploration MEPAG in Lisbon, Portugal (16-17 June 2011)