Download NRC Planetary Science Decadal Survey

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
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
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
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.
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
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


Plans for 2016, 2018 Missions relatively stable



2016 Trace Gas Orbiter, 2018 – Rover (Astrobio)
International collaboration developing


Life, Climate, Geology/Geophysics, Human Exploration
Exo-Mars, Mars Sample Return
Just had 1st meeting, briefings from MEPAG
community and mission studies.
Community white papers just delivered.
Process/Timeline

Sub panels meet, gather information, propose
missions for study.



Steering committee prioritizes input from subpanels into cross-solar system themes and goals.





Include “White papers” from community
Each sub-panel has 2 meetings between Aug-Nov 2009
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.
2003 Mars Themes / Key Questions

Mars as a potential abode of life


Water, atmosphere, and climate




Does/Did life exist, how habitable?
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
Why Mars?
1.
Mars offers crucial information about the early evolution,
internal structure, and origin of the terrestrial planets,
including Earth.
2.
Timeframe for evolution of life on Earth is largely absent
from the rock record, but this era is preserved on Mars.
3.
Mars provides a means to approach, and possibly answer,
origin and evolution of life questions.
4.
Excellent opportunity to investigate short- and long-term
climate change.
5.
Mars science has benefitted from a focused, dedicated
program of exploration.
MEP—An Integrated Set of Activities
Creating a True Program Structure
1996
Mars Global
Surveyor
2001
Year of Launch
2003
2005
2007
2011
Mars
Reconnaissance
Orbiter
Mars Odyssey
MAVEN
Curiosity
Opportunity
Spirit
Mars Pathfinder
2013
Phoenix
Strategic, Core Missions
Competitive PI-Led Missions
Advanced Planning & Community Input
Research and E/PO Programs
Base Technology
MER Focused Technology
MRO Focused Technology
MSL Focused Technology
10
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.
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
Smith
MRO
Lyell
Gilbert area
Victoria Crater
Hesperian subsurface water, diagenesis
-12
Past Decadal Results:
Wide variety of sedimentary deposits
Delta, showing phyllosilicate layers
Melas Chasma
MRO
MRO
MER
Meridiani
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
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
SHARAD and MARSIS
•
•
•
•
Nearly pure water ice
Distinct layering
No deflection of crust
Ice-cored lobate debris
aprons in mid-latitudes
PHX
MRO MEX
-14
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
Past Decadal Results:
Courtesy Mike Mumma
Modern Methane
NAI, R&A
courtesy Mark Allen
NAI
Detection of Methane on Mars
MEX NAI R&A
Abiotic?
Evidence of an
active subsurface?
Biotic?
courtesy Lisa Pratt
Past Decadal Results:
Mars Planetary Evolution
Neutral pH
Clays
Hydrous Mineralogy
Changed Over Time

acidic
Sulfates
Anhydrous Ferric Oxides
•
•
•
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
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)