HR: 16:45h
AN: P54A-04 INVITED     [Abstracts]
TI: Exploration of Titan by Balloon or Airship
AU: * Lorenz, R D
EM: rlorenz@lpl.arizona.edu
AF: Lunar and Planetary Lab, University of Arizona, 1629 E. University Blvd, Tucson, AZ 85721 United States
AB: Titan's surface is recognized as a focus for future exploration, yet Cassini shows it to be incredibly diverse - landers or even rovers to a handful of sites will not capture the range of phenomena and materials in this exotic landscape. Thus a platform able to access many widely-spaced locations on Titan is essential. Fortunately, Titan's low gravity and thick atmosphere lends itself to exploration by airborne vehicles such as balloons, airplanes, helicopters and airships. The latter vehicle type has received particular attention, since it combines `go to' ability to traverse to and stationkeep at targets of interest, while being, unlike heavier-than-air vehicles, `fail-safe' in terms of floating passively in an unpowered condition. In-situ analysis of surface chemistry can be performed using a tethered sampler. An airship or similar mission at Titan could be augmented by an orbiter, by remote sensing for mission planning and scientific context, by acting as a navigation beacon, and as a communications relay. However, none of these are essential. First, Cassini data allows the identification of target regions of interest at a level of a few kilometers - enough to know where the airship should explore further. Second, clear infrared windows in Titan's atmosphere permit the use of the Sun, Saturn and other targets as beacons for autonomous optical navigation at a large scale : optical odometry, correlation of landscape features with Cassini data, and the impressive Very Long Baseline Interferometry demonstrated by radio astronomers supporting Huygens may permit kilometer-scale location. Finally, while orbiter relay can increase the number of communication opportunities (depending on latitude) and the total data return, tens of megabits per day can be returned with direct-to-Earth communication. A portfolio of mission options therefore exists with a tradeoff of capability versus cost, from a passive balloon with direct-to-Earth only, to an airship with surface-sampling capability and a supporting orbiter. All of these options offer substantial scientific and public appeal, over a mission of genuine exploration that could last years at Titan.
DE: 5215 Origin of life
DE: 5405 Atmospheres (0343, 1060)
DE: 6281 Titan
DE: 6297 Instruments and techniques
SC: Planetary Sciences [P]
MN: Fall Meeting 2005