Cassini

Cassini

Cassini

Cassini used the gravitational effects of both Venus and the Earth to catapult itself across interplanetary space and reduce its journey time to Saturn to a mere seven years. It completed a flyby of the asteroid (2685) Masursky in January 2000 and swung by Jupiter in December 2000, picking up even more momentum in the process. During its Jupiter flyby, it teamed up briefly with NASA's Galileo probe in a joint investigation of the Jovian system. Cassini was scheduled to make 23 flybys of Saturn.

ESA's Huygens probe, carried aboard the Cassini spacecraft, was detached Dec. 24 2004 and landed on Titan Jan. 14 2005, after plunging into its dense atmosphere. During its parachute-controlled descent to the surface, which lasted about 2½ hours, and after touchdown, Huygens sent back a stream of data on the physics and chemistry of the satellite, including both pictures and sound. It transmitted from Titan's surface for about 70 minutes before its batteries ran out, and despite a computer malfunction aboard Cassini, which lost half the expected number of photographs, Huygens sent back via its mother ship about 350 pictures and a wealth of sensor readings. Ground-based radio telescopes also picked up some of Huygens' transmissions and rescued some science data that might have otherwise been lost. Preliminary analysis of the Huygens data appeared to confirm the view that Titan resembles the early Earth. Its atmosphere consists mostly of nitrogen, but concentrations of simple hydrocarbons such as methane exist near the surface. Evidence was found of liquid methane falling as ‘rain’ and penetrating just below the surfaces. At the Huygens landing site, the surface seemed to consist of a thin crust overlying a sandlike hydrocarbon soil; chunks of dirty water ice lay strewn nearby. High ridges were apparently cut by ‘river channels' draining down to lower terrain or even to a ‘lake’ of liquid hydrocarbons.