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Supernova origin clues found in dusty stellar wind ROYAL ASTRONOMICAL SOCIETY NEWS RELEASE Posted: April 5, 2005 Scientists from Imperial College London have detected a dusty wind emitted by a star that, at the end of its life, turned into a white dwarf and then exploded as a supernova. This is the first time that a wind from this type of supernova precursor has been observed and it is also the first time that associated dust has been detected. The properties of the wind hold vital clues to the kind of star that exploded. Dr. Rubina Kotak, from Imperial College London, will be presenting the discovery at the RAS National Astronomy Meeting at the University of Birmingham on Tuesday 5th April. The wind was detected around a Type Ia supernova, which is the kind of supernova used to measure the rate of expansion of the Universe. Type Ia supernova are sometimes referred to as "standard candles" because they have a predictable peak luminosity, which means that their observed brightness can be used to work out their distance from Earth. Although Type Ia supernovae have shown us that the expansion of the Universe is accelerating, there is still much we do not know about their nature and origin. To find out more about how supernovae explosions occur, scientists study the debris left behind and compare the observed concentrations of chemical elements with theoretical predictions. The team from Imperial, including Dr Kotak and Professor Peter Meikle, selected supernova SN 2002ic for study because it is the first Type Ia supernova in which hydrogen has been observed. Using the Very Large Telescope facility in Chile, the scientists precisely measured the speed at which the hydrogen was moving. They discovered that it was expanding much slower than expected, which indicated that they were seeing the undisturbed wind emitted by the star, prior to its supernova explosion. The scientists then obtained an infrared image of SN 2002ic taken with the United Kingdom Infrared Telescope on Mauna Kea (Hawaii) and found that it was incredibly bright. This infrared luminosity appears to be due to the dustiness of the wind from the star, and the subsequent heating of dust grains by the supernova explosion. The team from Imperial are continuing to monitor the behaviour of SN 2002ic using both ground-based telescopes as well as the Spitzer Space Telescope. Although it is not a typical Type Ia supernova, it should help scientists understand more about this important group of supernovae. Types of Supernovae SN 2002ic |
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Take a behind-the-scenes look at the seven astronauts who will fly aboard the space shuttle return-to-flight mission in this movie that profiles the lives of the STS-114 crew. (10min 04sec file)
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Walk alongside space shuttle Discovery as the motorized transporter hauls the ship a quarter-mile from the Orbiter Processing Facility to the Vehicle Assembly Building. (3min 21sec QuickTime file)
This time-lapse movie captured from an overhead camera shows space shuttle Discovery's middle-of-the-night departure from its processing hangar at Kennedy Space Center to the roll to the Vehicle Assembly Building. (4min 30sec file)
Discovery arrives in the Vehicle Assembly Building as viewed in this time-lapse movie. The shuttle will be mated to the redesigned external fuel tank and twin solid rocket boosters in the VAB before rolling to the launch pad for the first post-Columbia mission. (5min 00sec file)
A foot-long Russian nanosatellite is flung overboard by the spacewalking International Space Station Expedition 10 crew. Station cameras watched the hand-launched deployment and the nanosat as it floated away. (4min 52sec file)
Highlights of the second spacewalk of the International Space Station's Expedition 10 crew is compiled into this movie. The crew completed external outfitting of gear that will guide European cargo ships to the outpost during dockings starting in 2006. (5min 00sec file)
Mission managers preview the next spacewalk by the Expedition 10 crew aboard the International Space Station, which will install external equipment on the Russian segment and hand-launch a tiny nanosatellite. (37min 00sec file)
This video retrospective remembers the first flight of space shuttle Endeavour. The maiden voyage set sail in May 1992 to rescue the Intelsat 603 communications spacecraft, which had been stranded in a useless orbit. Spacewalkers attached a rocket booster to the satellite for the critical boost to the correct altitude.
This video retrospective remembers the 2002 mission of Columbia that made a long distance service call to the Hubble Space Telescope, giving the observatory a new power system and extending its scientific reach into the Universe. Astronauts performed five highly successful spacewalks during the mission.
This retrospective remembers the third voyage of space shuttle Columbia. The March 1982 mission served as another developmental test flight for the reusable spacecraft, examining performance of its systems while also conducting a limited science agenda. STS-3 is distinguished by making the first landing at Northrup Strip in White Sands, New Mexico.