This also includes investigation into whether and to what extent the ice masses are changing at the Earth poles. This question will be answered by Cryosat-2, a new research satellite being developed and built by Europe’s largest space company Astrium for the European space agency ESA. First hardware components have arrived in recent days at the Astrium satellite centre in Friedrichshafen, thus enabling the start of the mechanical integration of CryoSat-2. The satellite is expected to commence its space activities in March 2009.
Scientists assume that the polar ice masses will retreat considerably due to global warming; up to now, however, there is little selective data on these large, unpopulated and difficult-to-access polar regions. The radar satellite CryoSat-2 will remedy this information deficit and provide a global overview for researchers.
For at least three and a half years, CryoSat-2 will measure the thickness of sea-ice and changes at the land-ice margins with a precision previously unattained. The radar satellite data will help to pin down the connection between the melting of the polar ice and the rise in sea levels.
The first CryoSat was completed by Astrium in 2005. But because of a technical launcher defect, the satellite plunged into the Arctic Ocean during the launch attempt in October 2005. A few months later, ESA decided to build the satellite again. the design and configuration of CryoSat-2 are mainly based on CryoSat-1. Nevertheless, as many as 85 modifications are implemented in CryoSat-2.
Polar ice as a climate factor
Polar ice plays a key role in regulating the global climate. Despite being thousands of kilometres away from the most inhabited areas, the ice has a profound effect on the climate in Europe, Asia and the Americas. Three aspects are most important:
Firstly, the polar ice reflects a large portion of the sun‘s light. As polar ice melts, less sunlight is reflected, leading to the polar regions becoming warmer. Consequently, more ice begins to melt and the reflective capacity is further reduced. This could result in a self-accelerating cycle of global warming.
Secondly, open water radiates a large quantity of heat during the night. Thick sea-ice has a negative effect on this. To a certain extent, it acts as a thermal blanket and therefore plays a significant part in regulating the heat balance of the Earth.
Thirdly, melting polar ice can greatly affect the ocean currents with unforeseen consequences for the climate. They act as giant heat pumps, distributing the energy stored in the oceans around the globe. The best known example is the Gulf Stream, which transports warm water from the tropical latitudes across the Atlantic to northern Europe.
Radar provides more detailed views of ice
CryoSat-2 will circle the Earth in a polar orbit at an altitude of 720 kilometres. The special on-board radar instrument will provide data to determine the thickness and circumference of the polar ice sheets and sea-ice cover. Earlier radar satellites, such as the European ERS 1 and 2 or Envisat, are only equipped with a single antenna which enables them to gather information about uniform ice surfaces over a large area. CryoSat-2, on the other hand, has two antennas. Similar to the way in which humans, with two eyes, can see in 3-D, CryoSat‘s double radar will be able to scan the surface very precisely. This is called radar interferometry.
With this system, an average accuracy of one to three centimetres can be reached. Thus it can also collect data on non-homogeneous ice structures with very steep sides in the polar seas, glaciers or ice sheets. CryoSat-2‘s radar altimeter works day or night and can also penetrate clouds. Therefore, it is particularly suited to the research of the large polar ice sheets, which rise up to 4,000 metres above sea level and which are often covered by clouds. The data from the CryoSat mission will provide information about the rate of change of these huge ice sheets.
Astrium and CryoSat-2
Astrium, as the prime contractor for CryoSat-2, is responsible for a consortium of around 25 companies. Astrium in Friedrichshafen is building the satellite platform and integrating all instruments. Ultimately, Astrium is responsible to ESA for the reliability of the whole satellite. The industrial contract is valued at approximately €75 million.
Astrium, a wholly owned subsidiary of EADS, is dedicated to providing civil and defence space systems and services. In 2006, Astrium had a turnover of €3.2 billion and 11,000 employees in France, Germany, the United Kingdom, Spain and the Netherlands. Its three main areas of activity are: the business units Astrium Space Transportation for launchers and orbital infrastructure and Astrium Satellites for spacecraft and ground segment, and its wholly owned subsidiary Astrium Services for the development and delivery of satellite services.
EADS is a global leader in aerospace, defence and related services. In 2006, EADS generated revenues of €39.4 billion and employed a workforce of more than 116, 000.
Media Contact:
Mathias Pikelj
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Cryosat-2 Figures
Mass:
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Dimensions:
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4.6 x
2.34 x |
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Payload:
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Laser
retro-reflector |
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Star
trackers (3) |
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Height
resolution: |
1 to
|
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Horizontal
resolution: |
approx.
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Industrial
contract: |
approx.
75 million euros |
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Mission
duration: |
at
least 3,5 years |
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Orbit:
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|
||
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92
degrees inclination |
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Planned
launch date: |
March
15, 2009 |
(Source EADS Astrium)