Friday, October 4, 2013
Ralph D. Lorenz
Principal Professional Staff, Johns Hopkins University Applied Physics Laboratory
Oceanography is no longer just an Earth Science. The ongoing NASA/ESA Cassini mission - still making exciting discoveries 10 years after its arrival in the rich Saturnian system - has found that three seas of liquid hydrocarbons adorn Saturn's giant, frigid moon Titan. Titan was already exotic, having a thick, organic-rich atmosphere and a diverse landscape with mountains, craters, river channels, and vast fields of sand dunes, but these seas, and hundreds of lakes, present a new environment (low gravity, dense atmosphere, hydrocarbon liquid) in which to explore familiar and important physical processes such as air/sea heat and moisture exchange, and wind-driven currents and waves. Titan's seas (notably the two largest ones, Kraken Mare and Ligiea Mare, about 1000km and 400km across, respectively) thus are an appealing and accessible target for future Titan exploration.
This talk will review the latest findings from Cassini, the prospects for new discoveries as it moves towards Titan's northern summer solstice in 2017, and the opportunities for future exploration of Titan, not only with orbiters and landers but also with vehicles that can exploit Titan's air and liquid environments such as balloons, airplanes, and devices that float. In fact, the most affordable near-term prospect for in-situ exploration of Titan is a capsule that would float on Titan's hydrocarbon seas and drift in the moon's winds, traversing the sea, measuring liquid composition and turbidity, exploring the seabed, and providing visual imagery with a compact suite of meteorological instruments, a depth sounder, cameras and other instruments. This would be the first exploration of a liquid environment on a planetary body other than the earth.