XEUS mission hopes to win further ESA support Stakeholders have welcomed a decision to accept the X-ray Evolving Universe Spectroscopy (XEUS) project for further study in the European Space Agency's Cosmic Vision Programme. XEUS was one of eight potential future missions selected by the ESA Space Science Advisory Committe... Stakeholders have welcomed a decision to accept the X-ray Evolving Universe Spectroscopy (XEUS) project for further study in the European Space Agency's Cosmic Vision Programme. XEUS was one of eight potential future missions selected by the ESA Space Science Advisory Committee (SSAC) in October. 'We have been developing the XEUS concept for an advanced X-ray observatory for many years. This acceptance by ESA [the European Space Agency] is a major step forward for X-ray astronomers all over the world,' comments Professor Martin Turner of the Department of Physics and Astronomy at the University of Leicester. Professor Turner is the co-principle investigator on XEUS, as well as chair of the XEUS international steering committee. 'XEUS is an X-ray observatory 30 to 50 times more sensitive than XMM-Newton,' says Professor Turner, referring to the X-ray observatory X-ray Multi-Mirror Mission Newton, which was launched by ESA in 1999 and is the biggest scientific satellite ever built in Europe. XEUS is a follow-on to the XMM-Newton mission. 'The million degree universe, where gravity is the main source of energy, is the finest physics laboratory we have,' Professor Turner states. 'XEUS will help us find out about the behaviour of matter under extreme conditions of temperature, pressure and gravity. It will also let us study the influence of black holes on the formations of galaxies and stars; and ultimately planets and ourselves.' The new observatory would be placed 1.5 million kilometres from Earth, beyond the moon, at the second Lagrangian point. 'Because it is so large, the observatory has two spacecraft. The five-metre lens is in one, and the instruments in another. The two spacecraft fly together, 35 metres apart, to keep the instruments at the focus of the lens,' Professor Turner explains. If the XEUS study outcome is successful it will be launched on Ariane 5 from Kourou Space Centre in 2018. But before that, XEUS will have to beat the competing projects that address a wide range of issues, from the conditions for life and planetary formation to the structure and evolution of the Universe. Assessment of the projects will go on until 2011. At the end of the process, two missions will be proposed for implementation to ESA's Science Programme Committee. Most proposals were extremely mature, says Tilman Spohn from the German Aerospace Centre in Berlin, chairperson of the SSAC. He praised the 'excellence of the scientific community in Europe'. 'This made the task of the SSAC very difficult but we believe that the set of selected missions will shape the future of European space science. The next decade will indeed be very exciting for the scientific exploration of space.'
