Rosetta is an ESA mission designed to rendez-vous with Comet 67P/Churyumov-Gerasimenko, go into orbit around the cometary nucleus and also land a small probe on the cometary surface.
Launch occurred 2 March 2004 at 07:17 UT into a 200x4000 km parking orbit. About two hours later, at 09:14 UT, the upper stage was ignited to put the spacecraft on an escape trajectory. 18 minutes later Rosetta separated from the launch vehicle. En route Churyumov-Gerasimenko, Rosetta swung by the Earth on 4 March 2005, and will swing by Mars in February 2007, and then the Earth again twice in November 2007 and November 2009 for gravity assist. It will also make a fairly close fly-by of two asteroids, 2867 Steins in September 2008 and 21 Lutetia in July 2010. Arrival at Churyumov-Gerasimenko is scheduled for August 2014 at a heliocentric distance of 4.5 AU. It will then follow the comet while it progresses closer to the Sun and get a close-up view of the evolution of the cometary tail. (The mission was originally scheduled to fly to comet 46P/Wirtanen in February 2003, but had to be postponed because of problems with the Ariane 5 launcher. The postponement also meant that a different comet needed to be selected for the rendez-vous.)
Comets are primordial solar system objects that can be thought of as refrigators where the original solar system materia has been well kept. The comets that are currently in short-period orbits around our Sun have been kicked into their orbits from orbits much further away from the Sun by gravitational disturbances from the planets. Thus, it is only recently that they have been subjected to frequent thawing by solar irradiance. Therefore, the materia we now find in near-Sun cometary nuclei and in cometary tails is believed to be representative of the conditions in the early stages in the formation of the solar system. The main scientific objectives of the Rosetta mission are to study the origin of comets, the relationship between cometary and interstellar material and its implications with regard to the origin of the Solar System.
KTH participates as a science and hardware Co-Investigator in the Langmuir probe instrument (LAP) which is part of the Rosetta Plasma Consortium (RPC).
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For more information contact Lars Blomberg.