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Figure 3.1. - Titan Demonstration Mission. observation facilities or easy teleoperator control, yet is near enough for system monitoring and human intervention as part of a developmental process in the demonstration of a fully autonomous exploration technology. Such capability must include independent operation from launch in Low Earth Orbit (LEO); spiral Earth escape; navigation; propulsion system control; interplanetary flight to Saturn followed by rendezvous with Titan; orbit establishment; deployment of components for investigation and communication; lander site determinations; and subsequent monitoring and control of atmospheric and surface exploration and intensive study. The target launch date for the Titan Demonstration Mission was taken as 2000 AD with 5 years on-site. Knowledge gained from the Titan exercise could then be applied to the design of follow-on exploration missions to other planetary systems.

A number of specific criteria were decisive in the selection of Titan as a premier demonstration site for the autonomous exploration system concept:

(1) Titan is one of the few bodies in the Solar System where the physical and atmospheric conditions are partially unknown and interesting, but also still lie within acceptable tolerance ranges for equipment survivability.

(2) Titan, 9.54 AU distant from the Sun, is far enough from Earth to preclude intensive study using terrestrially based,scientific,experimental,and observational equipment, to deny easy teleoperator operations, and to require fully autonomous systems functioning while still being close enough for monitoring and intervention by humans as the demonstration experiment evolves.

(3) The existence of a heavy atmosphere provides a good test for system flexibility since atmospheric modeling