Titan Airship Explorer

Saturn's moon Titan is considered to be one of the prime locations for understanding the origins of life due to its rich environment of organic chemicals. A unique combination of dense atmosphere (more than four times that of the Earth), low gravity (one-sixth of that on the Earth) and small temperature variations makes Titan well-suited for studies with buoyant robotic vehicles (aerobots). Moreover, since the methane clouds obscure the entire surface, aerial platforms flying below the clouds are the only means of getting high-resolution global mapping of the Titan surface in the visible and infrared wavelengths. Major technical challenges for Titan aerobots include an extremely cold atmosphere (/spl sim/-90K), remoteness from the Earth (/spl sim/10 AU), which limit data transmission and prevents meaningful real-time control, and the consequent need for a high degree of autonomous operation. Remoteness from the Sun and obscuring cloud cover make nuclear energy the only practical source of power. Radioisotope thermal generators (RTGs) can provide sufficient power to give an aerobot limited propulsion capability. Propeller-driven aerobots are essentially airships that can move to specific targets on Titan rather than being constrained to travel with the prevailing winds. Such vehicles also can be used for in situ studies of the surface either through combined airship/rover concepts ("aerover") or through winching down an instrumented surface platform from a station-keeping airship. An airship baseline design is described including the key technical aspects of airship configuration, propulsion system, navigation and control concepts, data acquisition and communications. The resulting baseline design appears to be very attractive and suggests that airships are a good candidate for the post-Cassini exploration of Titan.