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What Is Astrobiology And Why Do We Care?. Bruce Jakosky Laboratory for Atmospheric and Space Physics University of Colorado at Boulder 9 February 2010. Earth. Mars. Venus. Europa. Enceladus. Places that meet/met requirements for life. Meet/met all requirements: Earth Mars Europa
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What Is Astrobiology And Why Do We Care? Bruce Jakosky Laboratory for Atmospheric and Space Physics University of Colorado at Boulder 9 February 2010
Places that meet/met requirements for life • Meet/met all requirements: • Earth • Mars • Europa • Meet some/most requirements and may meet all of them: • Enceladus • Ganymede • Callisto • Titan • May have met them in the past: • Venus • Io
Ongoing Mars Reconnaissance Orbiter Spirit and Opportunity Phoenix Cassini New Horizons MESSENGER Upcoming Mars Science Laboratory MAVEN JUNO Possible future missions Outer Planet Flagship Mars Sample Return Comet sample return Asteroid sample return Lunar South Pole / Aitken Basin sample return Particularly Relevant Spacecraft Missions
Potential Importance of the Role of Loss to Space • The history of liquid water and of the atmosphere determine Mars’ potential for life throughout time. • There is abundant evidence for climate change and atmospheric evolution. • Loss of atmospheric CO2, N2, and H2O to space has been an important mechanism for atmospheric evolution, and may have been the dominant mechanism. Only by understanding the role of escape to space will we be able to fully understand the history of the atmosphere, climate, and water, and thereby understand Martian habitability.
MAVEN Will Measure the Drivers, Reservoirs, and Escape Rates Plasma Processes Solar Input Neutral Processes • MAVEN will determine the present state of the upper atmosphere and today’s rates of loss to space. • Essential measurements allow determination of the net integrated loss to space through time.
Orbit Insertion: 16 Sept 2014 Ten Month Ballistic Cruise to Mars MAVEN Mission Architecture Launch: November 18, 2013 One Year of Science Operations
Launch Year Odyssey MRO Mars Express Coop MER Phoenix Mars Science Lab NASA’s Mars Exploration Program Operational 2016 2011 2009 2013 2018 & Beyond MAVEN Trace Gas Orbiter CU/LASP, GSFC, UCB/SSL, LM, JPL
Student perspectives on finding life elsewhere (1 of 2): • Finding bacteria elsewhere would be scientifically interesting, but only finding extraterrestrial intelligence would be truly profound. • It won’t make much difference to most people; their lives would go on pretty much as before. • We should solve our own problems here on Earth before we even go looking for life elsewhere. • Extraterrestrial intelligence will help us to save the world by solving all of our current problems. • Extraterrestrial life will destroy our civilization, either by intent or by accident.
Student perspectives on finding life elsewhere (2 of 2): • The existence of extraterrestrial life or intelligence would be inconsistent with the view of modern religions. • Modern religions have dealt with scientific discoveries and societal changes in the past, and they probably can adapt to deal with a discovery of life elsewhere (if there’s even a conflict). • We’ve already discovered extraterrestrial life and the government is hiding it, probably in a hangar in New Mexico. • We may not have discovered it yet, but the government is covering up anyway.
Searching for life elsewhere: Europa surface and ocean Mars sample return Extraterrestrial intelligence? Earth-like planets