from the European Space Agency...
14 January 2005
Today, after its seven-year journey through the Solar System on board the Cassini spacecraft, ESA’s Huygens probe has successfully descended through the atmosphere of Titan, Saturn’s largest moon.
The first scientific data arrived at the European Space Operations Centre (ESOC) in Darmstadt, Germany, this afternoon. Huygens is mankind’s first successful attempt to deliver a probe to another world so far away in the Solar System. This is a great achievement for Europe and its US partners in this ambitious international endeavour to explore Saturn.
The probe began transmitting data to Cassini four minutes into its descent and continued to transmit as long as it survived. Cassini started relaying data to Earth at 16:24 CET, which were picked up by NASA’s Deep Space Network and sent to ESOC in Germany, where the scientific analysis takes place.
Following its release from the Cassini mothership on 25 December 2004, Huygens reached Titan’s outer atmosphere after 20 days and a four-million-kilometre cruise. The probe started its descent through Titan’s hazy cloud layers from an altitude of about 1270 kilometres at 11:13 CET. During the next three minutes Huygens had to decelerate from 18 000 to 1400 kilometres per hour.
A sequence of parachutes then slowed down the probe to less than 300 kilometres per hour. At a height of about 160 kilometres the probe’s scientific instruments were exposed to Titan’s atmosphere. At about 120 kilometres, the main parachute was replaced by a smaller one to complete the descent, with an expected touchdown at 13:34 CET.
“Titan was always the target in the Saturn system where the need for ‘ground truth’ from a probe was critical. It is a fascinating world and we are now eagerly awaiting the scientific results,” says Prof. David Southwood, Director of ESA’s scientific programmme.
“The Huygens scientists are all delighted. This was worth the long wait,” says Dr. Jean-Pierre Lebreton, ESA Huygens Mission Manager. Huygens is expected to provide the first direct and detailed sampling of Titan’s atmospheric chemistry and the first photographs of its hidden surface, and will provide a detailed ‘weather report’.
One of the main reasons of sending Huygens to Titan is that its nitrogen atmosphere, rich in methane, and its surface may contain many chemicals of the kind that existed on the young Earth. Combined with the Cassini observations, Huygens will allow an unprecedented view of Saturn’s mysterious moon.
“Descending through Titan was a once-in-a-lifetime opportunity and today’s achievement proves that entrusting this to our European partners was the best choice,” says Alphonse Diaz, NASA Associate Administrator of Science.
The Cassini-Huygens mission is a co-operation between NASA, the European Space Agency and ASI, the Italian space agency. The Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology in Pasadena, is managing the mission for NASA’s Office of Space Science, Washington. JPL designed, developed and assembled the Cassini orbiter.
“The teamwork in Europe and the USA, between scientists, industry and agencies has been extraordinary and has set the foundation for today’s enormous success,” concludes Jean-Jacques Dordain, ESA’s Director General.
Huygens descent timeline
