"The supernovae make the chemical elements through real alchemy,mercurial vapor, transforming one element, the light elements into the heavy ones," he said. "So the calcium that is in your bones and the iron that is in your blood probably came from supernovae that exploded before the sun formed. So, we are all stardust,abercrombie, and it seems reasonable for us to want to know how these elements get formed when stars explode."(Www.hxen.com)The discovery of the young remnant does not immediately provide an answer to the puzzle,abercrombie and fitch, but scientists say it will be a "goldmine" to study, since it is still so recent and energetic. They say it is an important finding for understanding the life cycles of stars in the Milky Way galaxy.At a NASA news conference Wednesday,louboutin pas cher, scientists said they were able to estimate the age of the supernova by tracking its remnant's rate of expansion over the last 20 years. They say it expanded by 16 percent - a surprisingly large amount - indicating it is much younger than previously thought.supernova:超新星The scientist who led the study, Stephen Reynolds of North Carolina State University,doudoune moncler, said radio and X-ray technology allowed scientists to track the dying star through a dense field of gas and dust that had previously obscured the view.Supernovae and their remnants create and distribute the majority of the elements in the universe,louboutin, spreading everything from cobalt to gold."Large spiral galaxies like the Milky Way seem to have two or three per century,casque dr dre," he said. "But it is clear we have not been getting our share. A half dozen or so have been reported over the last millennium, but there should be 20 or 30. Now the galaxy is full of gas and dust, which could hide a distant supernova optically, but the remnant would still produce detectable radio waves and X-rays. This lack is a significant puzzle."Bob Kirshner, of Harvard University,abercrombie, explains why supernovae are important for all of us.Astronomers using NASA's Chandra X-ray Observatory and the Very Large Array radio telescope in New Mexico have discovered the remains of a supernova, known as "G1.9",casque beats, which must have lit up our galaxy with a bright flash of light about 140 years ago.The second most recent supernova is believed to have occurred around 1680. Ever since astronomers discovered that supernova more than 50 years ago, they have been searching for more "missing" supernovae and their remnants. Reynolds explains that scientists have measured the rates of exploding stars in other galaxies, and found out that our own Milky Way galaxy seems to be lagging behind in the number of supernovae per century.Download AudioScientists have announced the discovery of the youngest known exploding star, or supernova,mercurial, in our Milky Way galaxy. Astronomers say the remnant of the most recent supernova could provide clues to a long-standing mystery about why so few supernovae seem to explode in our galaxy, compared to other galaxies. VOA Correspondent Cindy Saine reports from Washington.相关的主题文章： http://www.flatsdb.com/forum/viewtop...=unread#unread http://www.ferzan.org/fanclup/index....17362#msg17362 http://www.netbazaar.jp/bbs/viewtopi...=unread#unread England manager Martin Johnson paid his respects in Christchurch on Wednesday, visiting the Lancaster Park pitch. Australia as well as the All Blacks will also visit.
06-04-2010, 01:19 AM
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