XMM- Newton ( engl: X - ray Multi - Mirror, that is X-ray multi-mirror ) is a space observatory of the European Space Agency ESA for observations in the X-ray range. It launched on 10 December 1999 aboard an Ariane 5G rocket from the Kourou Space Centre in French Guiana and stays according to plan until 2014.
The main task of XMM -Newton is the exploration of the most energetic processes in the universe. These include, for example, matter falling on black holes and " birth " and " death " of stars (see Supernova ).
The Ariane rocket brought the 3.8 -ton satellite in an eccentric orbit around the Earth with an equatorial inclination of 38.7 ° and a height of 850-114000 km. Further corrections to the onboard engine lifted the perigee 7,000 km. Such a train with about 48 hours turnaround time allows for long uninterrupted observations of variable objects and runs most of the orbital period outside of the interfering radiation belt of the earth.
XMM -Newton is constantly monitored by the European Space Operations Centre (ESOC ) in Darmstadt. Several radio antennas are used close to Perth ( Australia), Kourou and Santiago de Chile ( Chile). The collected data of the observatory will be prepared and administered by the XMM- Newton Science Operations Centre, Villafranca del Castillo (Spain).
The highly successful scientific mission was extended in 2005, 2007 and 2009. The final decision in November 2010 moved the mission end on 31 December 2014.
Telescope and experiments
The telescope was built by a European consortium under the leadership of the German DASA. XMM- Newton was the hitherto most massive satellite ever built and launched from Europe. Meanwhile, this record was surpassed but among others, the ESA satellite integral, which started in 2002 and supplemented by the observations of XMM- Newton in the gamma-ray range.
XMM -Newton has observed simultaneously three parallel-aligned X-ray telescopes of Wolter telescope type 1, the same territory. In order to increase the effective collection surface, each of these telescopes from 58 nested mirror shells thin but highly accurate. The focal length is 7.5 m and the diameter of the largest mirror shells 70 cm. Compared to the same time -driven X-ray Observatory Chandra NASA XMM-Newton has a much larger effective collecting area especially for hard X-rays at 7 keV, but a poorer picture quality of about 5 arcsec half- width for a point source.
XMM -Newton has three types of instruments:
- The three European Photon Imaging Cameras ( EPIC) were built under British management in Italy, France, Germany and the UK. Behind each of the three telescopes is an EPIC camera. One of the cameras uses a new type of pn-CCD, which was jointly developed by the MPI Semiconductor Laboratory of the Max Planck Institute for Extraterrestrial Physics with the company KETEK. The EPIC cameras provide X-rays in the range 0.1-15 keV and allow variability studies with high time resolution, as the arrival time of each photon is registered. Their energy resolution is based solely on the CCDs, and is relatively low, but sufficient for many purposes at about 1/ 20 to 1/ 50 of the photon energy.
- Reflection Grating Spectrometers The two (RGS ) were built under Dutch and American involvement. Through the use of an additional grating spectrometer they allow investigations brighter sources with much better energy resolution (1/ 200 to 1/ 800 of the photon energy ) in the energy 0,35-2.5 keV.
- The Optical Monitor is a telescope with a 30 cm diameter mirror which is mounted parallel to the three X-ray telescopes. It is the mission, the opportunity to examine their targets simultaneously with the X-ray observations in visible and ultraviolet light. It was developed in the UK.
The versatile XMM -Newton observatory has provided new results for different areas of astrophysics in the first 6 years of his life. These include
- Detailed X-ray spectroscopy of the corona of other stars than the sun.
- Studies of hot gas in galaxy clusters, showing that the previously suspected cooling flows in which the hot gas cools rapidly, so do not exist.
- The most sensitive recording sky hard X-ray light, with the development of active galactic nuclei can be studied in the early universe.