Mission Type: Orbiter
Launch Vehicle: Titan IVB/ Centaur
Launch Site: Cape Canaveral Air Force Station, Fla., USA
NASA Center: Jet Propulsion Laboratory
Spacecraft Mass: 5,712 kilograms (12,593 pounds) with fuel, Huygens probe, adapter, etc; 2,125 kilograms (4,685 pounds) unfueled orbiter alone
Spacecraft Instruments: 1) Composite infrared spectrometer; 2) imaging system; 3) ultraviolet imaging spectrograph; 4) visual and infrared mapping spectrometer; 5) imaging radar; 5) radio science; 6) plasma spectrometer; 7) cosmic dust analyzer; 8) ion and neutral mass spectrometer; 9) magnetometer; 10) magnetospheric imaging instrument; and 11) radio and plasma wave science
Spacecraft Dimensions: 6.7 meters (22 feet) high; 4 meters (13.1 feet) wide
Spacecraft Power: Three Radioisotope Thermoelectric Generators
Maximum Power: 885 watts (633 watts at end of mission)
Total Cost: About $3.27 billion, of which the U.S. contribution is $2.6 billion and the European partners' contribution $660 million
Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000, Monographs in Aerospace History No. 24, by Asif A. Siddiqi
National Space Science Data Center, http://nssdc.gsfc.nasa.gov/
Solar System Log by Andrew Wilson, published 1987 by Jane's Publishing Co. Ltd.
The Cassini-Huygens project was the result of plans at NASA dating from the early 1980s. The cooperative project involved a NASA-supplied spacecraft, Cassini, and a European Space Agency lander, Huygens. The lander was to study Titan, Saturn's largest moon, during a parachute descent.
During its four-year primary mission, Cassini used a large complement of instruments (including radar and optical imagers) to explore both Saturn and its many moons. The 3,132-kilogram orbiter, with a design life of eleven years, is powered by three RTGs.
Cassini's trip to Saturn included four gravity-assists. Seven months after launch, the spacecraft passed Venus on 26 April 1998 at a range of 284 kilometers, gaining 26,280 kilometers per hour. Cassini performed a second flyby of Venus on 24 June 1999 at a range of 600 kilometers and one of Earth at 03:28 UT on 18 August 1999 at a range of 1,171 kilometers; it then headed to Jupiter.
Cassini passed by the asteroid 2685 Masursky on 23 January 2000, coming close to a distance of 1.5 million kilometers at 09:58 UT. During the encounter, Cassini used its remote-sensing instruments to investigate the asteroid's size and dimensions, and albedo.
During the Jupiter encounter, on 30 December 2000, Cassini performed simultaneous observations of the planet with the Galileo orbiter.
Once past Jupiter, Cassini's was set for Saturn orbit insertion on 1 July 2004. Cassini was the first spacecraft to orbit Saturn. Pioneer 11 and Voyagers 1 and 2 were flyby missions.
On 24 December 2004, Cassini released the Huygens probe and continued its numerous flybys. The Huygens probe entered Titan's atmosphere on 14 January 2005. During its 2.5-hour descent, the spacecraft deployed a main parachute for stabilization and relayed data and images back to the orbiter for transmission back to Earth. It landed on rocky, muddy terrain and successfully sent back the first images from the surface of a moon beyond Earth's.
The orbiter continued its mission making numerous Titan flybys and capturing close looks at other moons, including Iapetus, Enceladus, Dione, Rhea and more distant encounters with Tethys, Mimas and Hyperion. Enceladus delivered one of the mission's greatest surprises -- geysers erupting from a moon previously thought to be frozen and inert. Scientists found the geysers create one of Saturn's rings.
The orbiter's primary mission ended on 30 June 2008. It is now on the Cassini Equinox Mission, seeking answer to new questions raised in Cassini's first years at Saturn. The mission's extension, through September 2010, is named for the Saturnian equinox, which occurred in August 2009 when the Sun shone directly on the equator and began to illuminate the northern hemisphere and the rings' northern face. Cassini observed seasonal changes brought by the Sun's changing angle on Saturn, the rings and moons, which were illuminated from the south during the mission's first four years.