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SYDNEY: A spectacular, rotating binary star system is a ticking time bomb, ready to throw out a searing beam of high-energy gamma rays – and Earth may be right in the line of fire. Astronomers at the University of Sydney, in Australia, first discovered the unusual and beguilingly beautiful star system eight years ago in the Constellation Sagittarius. One member of the pair is a highly unstable star known as a Wolf-Rayet, thought to be the final stage of stellar evolution to precede a cataclysmic supernova explosion. "When it finally explodes as a supernova, it could emit an intense beam of gamma rays coming our way", said Peter Tuthill, lead researcher of the team that report their findings in the current Astrophysical Journal. Vast and glowing plume At a distance of 8,000 light-years from Earth, the pair of stars are a short hop away in galactic terms, and just one quarter of the way to the centre of our Milky Way galaxy. The researchers took images of the system, known as WR 104, over a period of eight years using Hawaii's Keck Telescope. These images reveal a vast and glowing plume of heated dust and gas, billowing out in a spiral as the stars rotate once every eight months. This 'tail' is up to 30 billion kilometres long. But something curious about the images caught the attention of the experts. "Viewed from Earth, the rotating tail appears to be laid out on the sky in an almost perfect spiral. It could only appear like that if we are looking nearly exactly down on the axis of the binary system," said Tuthill. This means we are peering down the barrel of the gun, as when binary supernovae go off, all their energy is focussed into a narrow beam of wildly destructive gamma ray radiation that emanates (both up and down) from the poles of the system. "If such a gamma-ray burst happens, we really do not want Earth to be in the way," he said. "I used to appreciate this spiral just for its beautiful form, but now I can't help a twinge of feeling that it is uncannily like looking down a rifle barrel." Sterilising effect Though the risk may be remote, there is evidence that gamma ray bursts have swept over the planet at various points in Earth's history with a devastating effect on life. A 2005 study showed that a gamma-ray burst originating within 6,500 light-years of Earth could be enough to strip away the ozone layer and cause a mass extinction. Researchers led by Adrian Melott at the University of Kansas in Lawrence, U.S., suggest that such an event may have been responsible for a mass extinction 443 million years ago, in the late Ordovician period, which wiped out 60 per cent of life and cooled the planet. Further research would be required to determine if we are exactly in line with the axis of the system – but even if we are, we probably still have hundreds of thousands of years to come up with a solution, said Tuthill. with the University of Sydney
Readers' commentsMaybeMaybe, maybe not--maybe our sun's motion parallels this binary star's motion, so that we might be in its sights even longer. It might even fine-tune the pointing of the "barrel of the gun" in our direction. Given enough time, our solar system will be out of the blast path, but it would be nice if these or some other astronomers were to calculate how long it might take for the beneficial scenario to take place. Submitted by Visitor on 6 March 2008 - 2:22pm.
Rifle or shotgun?It could make a huge differenmce how much this burst spreads with distance. If it spreads more, a hit is more likely, but it would be less damaging. Though "less damaging" could still be at the bounce-the-rubble level of damage. Submitted by Visitor on 6 March 2008 - 6:17pm.
WatergunI think Hillary Clinton should send a firemen out there to extinguish the star. Submitted by Visitor on 7 March 2008 - 12:32am.
OzHillary thinks you should go see the wizard, get a brain. Submitted by Visitor on 30 March 2008 - 6:03pm.
Candidate ClintonShe graduated from Yale Law School - a school that has very tough academic standards for entrance. I read that she reads something like 50 books a week. She's articulate. Maybe people are afraid of her because she might include things such as social justice in her thinking. I personally would like to see us get away from being so nutso about national security and military spending and would like to see us advancing human rights in the world through our example. We could also stand to improve our infrastructure and increase the number of manufacturing jobs domestically. Hmm, she did vote to authorize the Iraq war, so I don't know about her. Submitted by Visitor on 31 March 2008 - 5:12am.
Clinton .....We called them Clintong50 books a week? You have a wrong source for information. People are not afraid of her. People did not forget what she is about. She is a communist, an enemy of our Republic. For their (Clinton) total involvement in making China a favored nation, and therefore opening a Pandora's box. Clinton's are responsible for selling hi-tech know-how to China. Now China is a superpower, USA is just a joke. China with their communist system, forced labor camps (called jails), violation of human rights on unprecedented scale, became a "favored nation to corporate America." Everyone knows Hillary Clinton is a man of the Clinton's house. Bill is just a puppet. Clinton's are the reason why all manufacturing moved out from the USA. Americans were replaced by the cheap slave labor in China. Almost all production in USA is dead now, we buy almost all products from China. Social justice? Are you one of these communists? We are the REPUBLIC, not a democracy as they - the soldiers of the Department of Education - are trying to brainwash you into believing. So, wake up! It is about Life, Liberty and Pursuit of Happiness. You have an unlimited right to contract. Do you understand that? There is nothing about a Social Justice! Never ever forget who push through and signed NAFTA. Clinton, McCain, Obama are same corporate politicians. They do not care about "We the People." The majority of all voters do not have any idea how corporate politics rules, while our "Creator given rights" are eliminated. Do you? Submitted by Visitor on 31 March 2008 - 12:23pm.
Clinton's death starI find it infinitely fascinating how a story about a star 8,000 light years from Earth can devolve into a political discussion involving Hillary Clinton. I’m fairly certain Hillary herself made that posting. I'm waiting for the next story about the Andromeda galaxy's imminent collision with the Milky Way to turn into a discussion about the separation between church and state. Submitted by Visitor on 1 April 2008 - 12:32am.
WHAT?How did this go from deathstars to the political forms? Submitted by Visitor on 22 April 2008 - 10:10am.
The Ancients KnewInstead of "looking down a rifle barrel", a more accurate description would be "looking down the shaft of an arrow". All of the ancient cultures of the earth had identical zodiacs with constellations and star names that have uniform meanings across all languages. E.W. Bullinger's book "The Witness of the Stars" is a good read for anyone who, like me, finds it strangely co-incidental that the source of this damaging shot of gamma rays will eventually come out of Sagittarius, "The Archer". In the constellation Capricorn there is also a star named "Sagittus" that the ancients termed "the arrow sent forth", which also symbolically brings Saggitarius to mind. People mock both the study of the bible and of "astrology" as irrational, superstitious purstuits. If you look at the evidence objectively, it is impossible to avoid the fact that all the ancient zodiacs and astrological records are based on a common source. The prophetic themes of the bible parallel the concepts contained in the ancient records. After the revelation was put in writing, people began to forget the truth of the original revelation that was associated with the constellations and "astrology" was perverted to the self-serving form of prognosticating that it is today. Originally it foretold something far more grand. People have done the same thing with the words of the bible, but the truth will make itself manifest. All of creation has had, and will have, trouble, pain and sorrow, but the Redeemer will come and we will all eventually find that it has been worth it. Submitted by Visitor on 7 March 2008 - 1:14am.
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Relative motion of our system and deathstar will save us
If we've got 100's of thousands of years before this thing blows, isn't it likely that differences in relative motion of our system and the "deathstar" will take us out of the line of fire?