NRC Planetary Science Decadal Survey

1. NRC Planetary Science Decadal Survey Wendy Calvin Prof. Geological Sci & Eng, University of Nevada - Reno Vice-Chair Mars Sub-Panel for Western Space Grant Directors Meeting DRI, 18.Sept.09

2. Decadal Surveys • Chartered by NASA, but provided by NRC as advisory arm of the NAS. • Independent assessment of scientific priorities in a given area. • Earth Science just completed (2007). • Astronomy/Astrophysics and Planetary currently underway. • Identify and Prioritize flight investigations believed to be > 450$M life cycle cost. • Include infrastructure, R&A, education, technology

3. New Frontiers in the Solar System (2003) • Fundamental Science Questions • 1st Billion Years of Solar System History • Volatiles and Organics stuff of life • Origin and Evolution of Habitable Worlds • How Planetary Systems Work • Example Recommended Missions • Europa Geophysical Explorer • Venus In-Situ • Jupiter Polar Orbiter • S. Pole Aiken (Lunar) Sample Return • Mars Network • Mars Sample Return

4. Planetary Science 2013-2022 • Overview of planetary science. • Survey the state of knowledge, recent discoveries. • Inventory top-level science questions that guide flight missions. • Small (Discovery), Medium (New Frontiers), Large (Flagship) mission classes. • (New) priorities for Mars and Earth’s Moon to be integrated with the rest of the Solar System. • (New) assessment and cost modeling of flight concepts. • (New) Astrobiology included in sub panels rather than separate sub-panel.

5. Committee Structure • Steering Committee (Squyres, Soderblom) • Vice-Chair of each sub panel (5) • 9 others not affiliated with any subpanel • Sub-Panels • Primitive Bodies (Asteroids, Comets, KBOs, Meteorites, IDPs) • Inner Planets (Mercury, Venus, Moon) • Mars • Giant Planets (JSUN, exoplanets, rings, fields) • Satellites (Europa, Ganymede, Titan Enceladus, and many, many others) http://sites.nationalacademies.org/SSB/CurrentProjects/ssb_052412

6. Mars Panel • 13 Members • Represent science from core to atmosphere • Strategic missions and design well-considered through MEPAG community process. • Goals and Objectives “Living” Document • Life, Climate, Geology/Geophysics, Human Exploration • Plans for 2016, 2018 Missions relatively stable • 2016 Trace Gas Orbiter, 2018 – Rover (Astrobio) • International collaboration developing • Exo-Mars, Mars Sample Return • Just had 1st meeting, briefings from MEPAG community and mission studies. • Community white papers just delivered.

7. Process/Timeline • Sub panels meet, gather information, propose missions for study. • Include “White papers” from community • Each sub-panel has 2 meetings between Aug-Nov 2009 • Steering committee prioritizes input from sub-panels into cross-solar system themes and goals. • Strive for consensus and community ownership • Fit within current budget constraints • Draft document from sub panels Spring 2010 • Draft full report Fall/Winter 2010 • External review and release of final report summer 2011.

8. 2003 Mars Themes / Key Questions • Mars as a potential abode of life • Does/Did life exist, how habitable? • Water, atmosphere, and climate • Sources, sinks, volatile reservoirs • Atm evolution, dynamics, atm escape • 3D distribution of water in the crust • Structure and evolution of Mars • Rock types, origin of crustal magnetism • Internal structure, core dynamo • Chronology, oxidation with depth

9. Why Mars? Mars offers crucial information about the early evolution, internal structure, and origin of the terrestrial planets, including Earth. Timeframe for evolution of life on Earth is largely absent from the rock record, but this era is preserved on Mars. Mars provides a means to approach, and possibly answer, origin and evolution of life questions. Excellent opportunity to investigate short- and long-term climate change. Mars science has benefitted from a focused, dedicated program of exploration.

10. MEP—An Integrated Set of ActivitiesCreating a True Program Structure Advanced Planning & Community Input MER Focused Technology Research and E/PO Programs Base Technology MRO Focused Technology Year of Launch 1996 2001 2003 2005 2007 2011 2013 Mars Reconnaissance Orbiter MAVEN Mars Global Surveyor Mars Odyssey Curiosity Opportunity Phoenix Spirit Mars Pathfinder Strategic, Core Missions Competitive PI-Led Missions MSL Focused Technology 10

11. Last Decade Discoveries: Diverse Planet with Complex History • Mars has areas with diverse mineralogy, including alteration by water, with a change in mineralogy over time and spatial diversity of environments. • In situ confirmation of increased water activity in the past. • Pervasive water ice in globally distributed, near-surface reservoirs. • Sources, phase changes, and transport of volatiles (H2O, CO2) are known & some are quantified. • Increasing evidence for geologically recent climate change. • Dynamic change occurring even today: landslides, new gullies, new impact craters, changing ice cover. • Presence of methane indicative of active chemical processes either biogenic or abiotic. • Based on much of the above, the perception of Potential for past Life has increased, and Modern Life may still be possible.

12. Last Decade Discoveries: Diversity of Environments PHX • Chemistry and morphology indicate changing environments throughout geologic history • Acidic waters at Meridiani • Basic waters at Phoenix landing site • Mineralogy: clays to sulfates to oxides MER Steno MRO Smith Lyell Gilbert area Victoria Crater -12 Hesperian subsurface water, diagenesis

13. Past Decadal Results: Wide variety of sedimentary deposits Delta, showing phyllosilicate layers Melas Chasma MRO Meridiani MER MRO Large-scale sedimentary structures • Depositional processes created a sedimentary record • Developed in topographically low areas • Spectacular stratification at multiple scales • Evidence of persistent standing water, lakes • Sediments systematically change in character with time • Multiple facies recognized Eberswalde Delta Fine-scale sedimentary structures -13

14. Past Decadal Results: Distribution of Modern Water Global Near-Surface Reservoirs of Water ODY Gamma Ray Spectrometer • Global hydrogen abundance and equivalent H2O • Ground ice to +/-60° in high abundance Phoenix results PHX SHARAD and MARSIS • Nearly pure water ice • Distinct layering • No deflection of crust • Ice-cored lobate debris aprons in mid-latitudes MRO MEX -14

15. Past Decadal Results: Periodic Climate Change •Latitude dependent mantle Modeled Ice Table Depth [m] • Volatile-rich, latitude dependent deposits (mantle, glaciers, gullies, viscous flow) coupled to orbitally-forced climate change • Periodicity of layering in the north polar cap deposits as well as sedimentary deposits MGS, ODY, MEX MRO

16. Past Decadal Results: Modern Methane courtesy Mark Allen NAI, R&A Courtesy Mike Mumma NAI Detection of Methane on Mars MEX NAI R&A Abiotic? Biotic? Evidence of an active subsurface? courtesy Lisa Pratt

17. Past Decadal Results: Mars Planetary Evolution • Hydrous Mineralogy Changed Over Time • Phyllosilicate minerals (smectite clay, chlorite, kaolinite…) formed early • Evaporates dominated by sulfate formed later with opal/hydrated silica • Few hydrated mineral deposits since • Evolution of Aqueous, Fluvial and Glacial, Morphology with Time • Valley networks, lake systems • Gullies • Viscous flow, glaciers, latitude dependant mantle Neutral pH acidic Clays Sulfates Anhydrous Ferric Oxides

18. Questions for the Next Decade Integrating the MEPAG science priorities and the programmatic factors, these specific questions are highest priority for the next decade. What is the diversity and nature of aqueous geologic environments? (Goal I, II, III--MSL will contribute) What is the detailed mineralogy of the diverse suite of geologic units and what are their absolute ages? (Goal II, III) Are reduced carbon compounds preserved and, if so, in what geologic environments? (Goal I--MSL may contribute) What is the complement of trace gases in the atmosphere and what are the processes that govern their origin, evolution, and fate? (Goal I, II, III) How does the planet interact with the space environment, and how has that affected its evolution? (Goal II—addressed by MAVEN mission) What is the record of climate change over the past 10, 100, and 1000 Myrs? (Goal II, III) What is the internal structure and activity? (Goal III)