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XMM-Newton survey shows secrets of the X-ray sky ROYAL ASTRONOMICAL SOCIETY NEWS RELEASE Posted: April 4, 2006 The European Space Agency's XMM-Newton X-ray observatory has already been a spectacular success in many areas of astronomy - detecting distant clusters of galaxies, the faint afterglow of enigmatic gamma ray bursts and the effects of the collision of the Deep Impact probe with comet Tempel-1. Now an innovative new approach analyses X-rays detected during the times that the satellite manoeuvres between targets - originally considered to be unusable periods - to reveal some 4,000 intensely brilliant X-ray stars and galaxies. An initial study has identified these with a host of highly energetic celestial phenomena. These include close binary stars, where matter is being pulled away from one star to explode onto the surface of the companion; and distant quasars, super-luminous galaxies up to 10 billion light years from Earth, which are being slowly consumed by a voracious central black hole. Preliminary results from this study, known as the XMM-Newton Slew Survey, will be presented today (Tuesday) at the RAS National Astronomy Meeting in Leicester by Dr. Andy Read of Leicester University. XMM-Newton, with the huge collecting area of its many nested mirrors and the excellent efficiency of its EPIC X-ray camera/detector, is the most sensitive X-ray observatory ever flown. As a result, it is able to record unrivalled numbers of X-rays from the cosmos. Since its launch in December 1999, XMM-Newton has observed thousands of objects, gazing at a particular X-ray source for hours, before turning or "slewing" away at a great speed to observe its next target. Since September 2001, the XMM-Newton 'shutter' has been open during these slews, and this has yielded hundreds of extremely long snapshot strips of the X-ray sky. Though the slews are so quick that XMM-Newton passes over each point in the sky in only 10 seconds (compared to a normal "pointed" observation of a few hours), this 10 second exposure is enough time for XMM-Newton to detect thousands of sources in the sky. "The area of the sky that is covered is enormous," said Andy Read. "Over a quarter of the entire sky has already been covered in the 400 or so slews so far performed, and many more slews are continually taking place. The entire sky will be covered - even at the present extremely slow rate - over the lifetime of the XMM-Newton mission. As such, this XMM-Newton slew survey, even coming as it does, for 'free', rivals the best of all previous dedicated all-sky X-ray surveys. For detecting high-energy X-rays, it is certainly the best that there has ever been." "A wonderful variety of X-ray sources has been seen in the Slew Survey, including black holes, quasars, active galaxies and stars - many of which have been observed for the first time." Only a survey such as this, covering such a large area of the sky, is able to observe the rarest of events. The team involved in the survey has, for example, seen a number of X-ray sources undergoing extraordinary changes in brightness, events that are thought to be due to stars being captured whole by massive black holes. The best example is an otherwise normal galaxy, about 40 million light years away, which has been seen to increase remarkably in X-ray brightness (possibly linked to matter being drawn into a supermassive central black hole). "This galaxy is far, far brighter than it was when previously observed with older X-ray satellites," said Dr. Read. Furthermore, the great sensitivity and low "noise" of the EPIC CCD camera is especially suited to detect emission from extended sources that cover a large area of space, and many extremely interesting supernova remnants and massive clusters of galaxies have been observed. "Multi-slews that are criss-crossing large areas of the sky are now giving us new, large-scale views of the biggest X-ray objects in the sky," said Andy Read. Other members of the XMM-Newton Slew Survey team are: Richard Saxton (ESAC, Spain); Pili Esquej (MPE, Germany / ESAC, Spain); Dr. Michael Freyberg (MPE Germany); and Dr. Bruno Altieri (ESAC, Spain). The European Photon Imaging Camera (EPIC) was developed by a consortium led by the University of Leicester, UK. The 2006 RAS National Astronomy Meeting is hosted by the University of Leicester. It is sponsored by the Royal Astronomical Society, the UK Particle Physics and Astronomy Research Council (PPARC), the University of Leicester and the National Space Centre, Leicester. |
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The Russian Soyuz TMA-8 spacecraft carrying the Expedition 13 resident crew successfully docks to the Zarya module of the International Space Station under automated control.
Full coverage of the Expedition 13 crew's launch aboard a Russian Soyuz spacecraft to begin a six-month mission aboard the International Space Station.
External cameras on the International Space Station captured this incredible footage of the March 29 solar eclipse. The station flew through the eclipse over the Middle East as the moon passed in front of the sun and cast its shadow on the Earth.
A total solar eclipse occurred March 29. This video from Side, Turkey shows the period of totality when the moon slid between the Earth and Sun. The eclipse revealed the Sun's glowing outer halo of million-degree gas, called the solar corona.
In early March, NASA cancelled its Dawn mission built to orbit two of the solar system's largest asteroids using ion engine propulsion. Technical problems and cost overruns were blamed. But in this news conference from March 27, agency officials announce NASA's decision to reverse the cancellation and restart the mission.
Lockheed Martin holds this news conference in Houston on March 24 to announced that it is partnering with the State of Texas to locate the Crew Exploration Vehicle (CEV) program office in Houston, as well as systems engineering, software development and qualification testing, if the corporation wins the NASA contract to build the next generation spacecraft for NASA.
As the Expedition 12 mission aboard the International Space Station winds down, officials managing the flight from Mission Control in Houston hold this retrospective briefing to talk about the highs and lows, the science, the spacewalks and everything in between.