Clusters of galaxies, centres of galaxies, quasars - even normal stars like the Sun - all emit X-rays. These rays offer a wealth of chemical and physical information about cosmic objects. X-rays are absorbed by the air molecules in the Earth’s atmosphere; they can therefore only be examined by satellite outside the Earth’s atmosphere.
The European satellite XMM-Newton (X-ray Multi Mirror), built under contract to ESA by a consortium of 35 European companies with Astrium as prime contractor, by far excels its predecessor, the Astrium-built Rosat satellite. The telescope contains three identical X-ray mirror systems thereby attaining a very high degree of sensitivity.
XMM-Newton is the largest European science satellite ever built. After launch by an Ariane 5 in December 1999, the first pictures taken by XMM-Newton were received in February 2000. The telescope continues to send a wealth of new information about the source of X-rays and although the original mission lifetime was two years, it has a total 10-year life expectancy.
