Thursday, April 9, 2009

Is a Death Star Poised for Final Supernova Detonation Aimed at Earth? Astronomers Say "Maybe"

Death_star Australian astronomers have been studying an intergalactic assassin poised to wipe out life on Earth. Maybe. Observations indicate that cosmological curiosity WR104 may be a killer - and we might be the victim.

The pretty pinwheel that makes the system so distinctive is now know to be a combination of two stars - a blue star orbiting the Wolf-Rayet 104. Note that the "Wolf-Rayet" name is the astronomical equivalent of a beeping red LCD countdown reading "0:01" - it's a swollen star getting ready for final supernova detonation. At the moment its fusion reactions are blasting its own photosphere off into space, where the blue companion orbits and illuminates the material, creating a seriously impressive spiral over twice the size of our solar system.

We have a perfect view of this pinwheel pattern, since the spiral is at right angles to us, in the same way a man being held at gunpoint has a perfect view of the little hole the bullets come out of. And the gun is over twenty-five times the size of the sun. When a binary system collapses into a black hole, which astronomers call 'coalescence' (a euphemism which makes 'heated debate' a valid description of World War II), it can release a gigantic burst of gamma rays. Gamma rays are the ultimate high energy electromagnetic radiation, and while the burst lasts less than two minutes it can contain more energy than the entire mass of the sun converted into energy by E = m c^2. You'll notice that the mass of the sun and the speed of light, c, are extremely large numbers.

On the upside we'll never see it coming. The EM-burst travels the speed of light so the only warning we'd have is dying - which most people will accept is a little too late. The dinosaurs certainly did (some scientists believe historical mass extinctions were caused by similar intergalactic "life reset button" gamma bursts). Even better, this Earthicidal explosion may have already happened with the lethal radiation already speeding its way right at us. On the other hand, the big boom might not happen for hundreds of thousands of years - and might do so without a peep of gamma radiation.

The combination of science and philosophy is a challenging field that many don't bother with, but this is a strong motivation to start. If you could die tomorrow, how would you like to live today?

Posted by Luke McKinney.

Original here

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