Transcript Mars - Department of Earth and Planetary Sciences, WCAS

Mars
Elena Zhang and Karen Tekverk
http://www.nasaimages.org - Mars: Closest Approach 2007
Background Information
•
•
•
•
•
•
•
Mass: 6.42 x 1023 kg or 0.11 Earths
Distance from Sun: 1.524 AU
Radius: 3390 km or 0.53 Earth radii
Average density: 3.93 g/cm3
0.38x Earth’s gravity at surface
0.006x Earth’s atmosphere at surface
Atmospheric composition:
–
–
–
–
95.3% CO2
2.7% N2
1.6% Ar
0.4% other
(Adapted from Planets and Life Table 18.1, page 358)
http://www.nasaimages.org - Mars
Background Information
• Dense core of indeterminate size – either small dense Fe core, or
larger less dense FeS core
• No global-scale plate tectonics, but some tectonic processes –
volcanism (Tharsis), grabens and faults (Valles Marineris)
• Evidence for liquid water on ancient Mars surface
• There are a few dozen Martian meteorites that have landed on the
Earth, know collectively as SNC meteorites, and ALH84001
• Composition of Martian crust (from Viking analysis):
–
–
–
–
–
–
–
–
43.4% SiO2
18.2% Fe2O3
7.2% Al2O3
7.2% SO3
6.0% MgO
5.8% CaO
1.34% Na2O
~3% other
http://www.nasaimages.org - Mars
Mars Flyover
http://www.nasaimages.org - Mars Flyover based on MOLA
Data for the Carl Sagan Lecture, NASA/Goddard Space Flight
Center Scientific Visualization Studio
• First shown: South Pole
• Three linear volcanoes:
Tharsis Rise
• North Pole
• Largest volcano:
Olympus Mons
• Valles Marineris
• Colors illustrate 22 km
of altitudinal variation –
blue is the lowest
Previous Exploration
Landmarks and Other
Spacecraft
• Viking 1 and 2, 1975, first
to land on surface and
take images
• Mars Observer, 1992,
orbiter
• Climate Orbiter, 1998,
weather satellite
• Polar Lander / Deep
Space 2, 1999, lost on
arrival
Planets and Life, page 358
Current Missions
Pheonix
•Launch: Aug 4, 2007
•Arrival: May 25, 2008
•Dig up and analyze icy soil at north polar
region
Mars Reconnaissance Orbiter
•Launch: Aug. 12 2005
•Arrival: Mar. 10, 2006
•Telescopic camera
Mars Exploration Rovers
•Spirit Lauch: Jun 10, 2003 – Arrival: Jan 3,
2004
•Opportunity Launch: Jul 7, 2003 – Arrival: Jan
24, 2004
•Search for evidence of liquid water
Mars Express
•Launch: Jun 2, 2003
•Arrival: Dec 2003
•Explore atmosphere and surface
from polar orbit
Mars Odyssey
•Launch: Apr 7, 2001
•Arrival: Oct 24, 2001
•Orbiting spacecraft, determine
composition of surface, detect
water and shallow buried ice,
study radiation environment
Future Missions
Mars Science Laboratory
•Launch: Fall 2011
•Arrival: 2012
•Curiosity Rover, 2x long, 3x heavy as
previous rovers
•Over $2.5 billion
•Collect soil samples, rock cores, analyze
for organic compounds and
environmental conditions that could
have supported microbial life
Mars Atmosphere and Volatile Evolution
(MAVEN)
•Launch 2013
•Arrival: 2014
•Atmosphere, climate history, potential
habitability
Previous Claims of Life on Mars
• “Canals” (so named by Percival Lowell)
• Blueberries (actually hematite
spherules)
• Crinoids (actually water features)
• “The Couch”
http://www.nasaimages.org Terrain and rock “Couch”
http://www.nasaimages.org - Two Types of
Round Pebbles in ‘Endurance’, NASA/JPL/Cornell
http://apod.nasa.gov/apod/ap031112.
html - Mars Then And Now
www.imdb.com
Characteristics of Planetary Life
• Elemental building blocks of life – C, H, O, N…
• Molecular building blocks of life – amino
acids, sugars
• Life begins to exist quickly after it becomes
possible
• Environmental requirements for life
straightforward and widespread
• Almost any geologically active planet could
foster life, including Mars
Previous Evidence for Martian Life
• Spirit Rover
• Comanche rock outcrop rich in carbonates
found in Gusev Crater
• Could be due to aqueous processes, or
volcanic activity
http://www.nasaimages.org - MOLA-based Flyover of Gusev Crater,
NASA/Goddard Space Flight Center Scientific Visualization Studio
Previous Evidence for Martian Life
• Spirit Rover
• Stratified soil layers with different
compositions
• Snow melt might have carried soluble
minerals (ferric sulfate) lower than less soluble
minerals (hematite, silica, gypsum)
http://www.nasaimages.org - Sprit Stuck in Soft Soil as
Engineers Devise Methods to Free Spirit
Previous Evidence for Martian Life
• Methane gas identified in 2003-2004
• Active hot spots of methane
• Chemical processes rapidly destroy methane
(oxidizing agents)
• Source: could be geology (water and rock) or
biology
• Next step: test abundance of molecular trace
species, isotopic analysis (MSL)
Previous Evidence for Martian Life
• 300 billion year old deposits of hydrated silica found on
volcanic cone (by Mars Recon Orbiter)
• Silica can be transported, dissolved, and concentrated by
hot water or steam
• Indicates possible hydrothermal environment (hot spring)
Cost of Current Missions
Phoenix
•$325 million
Mars Reconnaissance Orbiter
•Total cost: $720 million
•Cost of spacecraft and science
instruments: $450 million
•Launch: $90 million
•Mission operations: $180 million
Mars Exploration Rovers
•Total cost of building, launching, landing,
and operating for initial 90-day mission:
$820 million
•Four mission extensions = $104 million
•Fifth mission extension = at least $20
million
Mars Express
•Total cost: About $369 million
•Orbiter: About $179 million
•Lander: About $95.5 million
Mars Odyssey
•Total cost: About $300 million
•Development and construction: $165
million
•Launch: $53 million
•Operations: $79 million
http://www.nasaimages.org - Mars Odyssey
Seen by Mars Global Surveyor, NASA/JPL/MSSS
NASA’s Proposed Budget for 2012
(in millions of dollars)
2012
2013
2014
2015
2016
2009 Mars Science Lab
138.0
42.0
38.5
0.0
0.0
MAVEN
245.7
146.4
37.6
17.3
5.3
Other missions and data
analysis
218.6
253.0
337.9
294.6
241.9
Total Mars Exploration
602.2
441.4
414.0
311.9
247.2
Total NASA budget
18,724.3
Our Proposed Budget
• For an orbiter and rover (there and back):
Approximately $2.7 billion
• About 14% of NASA’s total 2012 budget
(or, for reference, about 0.4% of
Department of Defense’s 2011 budget)
• Ways to cut costs:
» Wait for a return on information from the Mars
Science Laboratory, designed to give a better
background on how and where life might have
existed on Mars
» Allow for contractors to have rights to anything
patented in the process
http://www.nasaimages.org - The Beagle 2 lander, ESA