HR: 1830h
AN: P45A-01 INVITED    [Abstracts]
TI: Sagan Lecture : Exploring Titan, An Earth-like Organic Paradise
AU: * Lorenz, R D
EM: ralph.lorenz@jhuapl.edu
AF: JHU Applied Physics Laboratory, 11100 Johns Hopkins Road, Laurel, MD 20723, United States
AB: Saturn's giant moon Titan has been called many things – 'The Mars of the Outer Solar System', 'A Fiercely-Frozen Echo of the Early Earth', 'A Place Like Home'- indeed, 'The Whole ball of Wax'. These various appelations reflect the richness and bewildering complexity of this most fascinating world which bears comparisons with both the terrestrial planets as well as other icy satellites. Titan's thick but dynamic atmosphere sculpts its surface with tidal winds and methane monsoons, and its climate has competing greenhouse and antigreenhouse effects as well as a seasonal polar haze structure analogous to the Earth's ozone hole. Titan is striking also in its massive organic inventory – its dunes and lakes make up an exposed carbon reservoir hundreds of times more massive than all of Earth's fossil fuels. At least part of this organic inventory has been processed by transient exposures to liquid water, in impact melt sheets and cryovolcanic flows (a scenario first pointed out by Thompson and Sagan in 1991). This aqueous chemical interaction is known from terrestrial laboratory experiments to yield amino acids, pyrimidines and other building blocks of living molecular systems. How far these chemical systems might evolve on geological, as opposed to laboratory, scales of space and time on Titan is completely unknown, but must surely be interesting to find out. The talk will review some of the surprising findings from Cassini-Huygens, their lessons for us here on Earth, and what future Titan exploration may tell us about the origins of worlds and the origins of life.
UR: http://www.lpl.arizona.edu/~rlorenz
DE: 5210 Planetary atmospheres, clouds, and hazes (0343)
DE: 5215 Origin of life
DE: 6281 Titan
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting