The First Flexbus Small Satellite of Astrium:
Potsdam/Friedrichshafen — For a period of five years, the German research satellite Champ, developed and built by Jena-Optronik GmbH and Astrium GmbH (Friedrichshafen), will deliver important data for fundamental geoscientific research and physics of the atmosphere. The launch from the Russian launch site Plesetzk, 800 kilometers north of Moscow, with a Cosmos booster is scheduled for mid-July.
Champ will provide data on the composition, structure and dynamics of the solid planet, its oceans and atmosphere as well as the surrounding envelope of charged particles and magnetic fields. For this purpose, various sensors such as a magnetometer, accelerometer, digital ion drift meter and a laser retroreflector are mounted on the satellite and its four-meter boom.
On its orbital track, Champ will orbit the Earth every 93 minutes The route will be exactly above the poles. Similar to a globe on an axis, the Earth will rotate below its orbit, thus enabling a precise measurement.
One of the mission objectives is to further develop the existing gravity model of Earth. This enables exact measurements of the mass changes on the Earth’s surface — for instance, by assumed polar ice melting. These can then be used for drawing conclusions on climatic changes. In addition, the German meteorological service will benefit from the measurement of atmospheric parameters allowing more precise forecasts.
The exact and spatial measuring of Earth gravitation will enable the scientists to determine miniscule differences of levels in the oceans’ surface. The high-accuracy measurement of the Earth’s magnetic field is one of the tasks of Champ because scientists have detected a continuous decrease in the magnetic field’s strength over the past 400 years. This could be an indication for a polarity reversal of the Earth’s magnet. Such magnetic polarity reversals occurred time and again in the history of Earth. Stones containing magnetic minerals are an evidence of this. As the magnetic field protects us against so-called cosmic radiation — i.e. high-energy particles from space — the researchers have a special interest in this phenomenon.
Exact magnetic field measurement also gives an insight into the Earth’s interior as the magnetic signals indicate mass movements within the Earth. Thus, geophysicists hope for a more in-depth investigation of the driving force of continental drifts and they are convinced that their findings can be made available for broad applications. Thus, the exact knowledge of the magnetic field can be used for the navigation of ships and aircraft or the alignment of deep-well drilling to the field line course.
Furthermore, Champ is to be used for investigating the atmosphere. For this purpose, it records the signals of so-called GPS satellites via its radio wave receiver. If the GPS partner of Champ is on the other side of Earth, the radio waves must travel through the Earth’s atmosphere. And exactly this feature is used by the scientists. In the atmosphere, the signals are changed in the air, they are refracted or delayed. On the basis of these changes weather researchers may reconstruct parameters, such as temperature and pressure.
Champ is a comparably affordable small satellite project; this has been made possible by the Flexbus concept of Astrium: Flexbus is based on a mature basic architecture for the spacecraft bus combined with components already proven in space missions and individual, mission- specific components. Satellites developed and built on the basis of Flexbus can be placed into orbit already two to three years after receipt of order. In addition to development and testing for a mission, this concept also facilitates satellite operation.
The research satellite Champ is a project of the geophysical research center in Potsdam (GFZ) and the German aerospace center (DLR).
Jena Optronik GmbH, a subsidiary of Europe’s new  aerospace company Astrium, was responsible for building the satellite.
For further information:
Earth Observation & Science
Mathias Pikelj
Tel.: +49-7545-8-9123
Fax: +49-7545 8-5589