Rosetta
The International Rosetta Mission was approved in November 1993 by ESA's Science Programme Committee as the Planetary Cornerstone Mission in ESA's long-term space science programme. The mission goal is a rendezvous with comet 46 P/Wirtanen. On its eight-year journey to the comet, the spacecraft will pass close to two asteroids (Otawara and Siwa are now the planned targets).
The spacecraft will also carry the Rosetta Lander (Surface Science Package) to the nucleus and deploy it onto the comet's surface. The Lander is provided by a German-led consortium of European institutes.
Rosetta will study the nucleus of comet Wirtanen and its environment in great detail for a period of nearly two years, the near-nucleus phase starting at a heliocentric distance of about 3.25 AU, with far-observation activities leading ultimately to close observation (from about one km distance).
Rosetta was launched in January 2003 by an Ariane-5 from Kourou, French Guiana.
The MIDAS Scanning Electron Microscope
The Orbiter's scientific payload includes 11 experiments. One of these, the MIDAS (Micro-Imaging Dust Analysis System) studies the dust environment around the asteroids and comet. It provides information on particle population, size, volume and shape.
The Space Systems Group's invlovment in MIDAS is in data compression. In order to reduce the amount of data transmitted to ground, the MIDAS data is preprocessed onboard, reducing a large fraction of the images to derive feature vectors.