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A Cosmic Death, 2.7 Billion Light Years Away


Heretic

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May 5, 2012 — Astronomers have gathered the most direct evidence yet of a supermassive black hole shredding a star that wandered too close.

NASA's Galaxy Evolution Explorer, a space-based observatory, and the Pan-STARRS1 telescope on the summit of Haleakala in Hawaii were among the first to help identify the stellar remains.

Supermassive black holes weigh millions to billions times more than the sun. They lurk in the center of most galaxies, waiting for an unsuspecting victim - such as a star - to wander close enough. They are then ripped to shreds by the powerful gravitational clutches of the black hole.

This video is a computer simulation of the "celestial homicide", demonstrating a star being shredded by the gravity of a massive black hole. Some of the stellar debris falls into the black hole and some of it is ejected into space at high speeds.

The areas in white are regions of highest density, with lower-density regions becoming progressively redder. The tiny blue dot in the top right hand corner pinpoints the black hole’s location.

The elapsed time, almost half a year, corresponds to how long it takes for a sun-like star to be ripped apart by a black hole a million times more massive than the sun.

More here including the computer simulation:

http://www.theweathe...ther_topstories

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I'm guessing this is because the entire star did not cross the event horizon instantly. If one of the objects (star or black hole) were moving at a very high speed directly towards the other then the star may have a chance at hitting the event horizon at a roughly perpendicular angle and being 'sucked in', but we usually speculate objects will orbit the black hole for a time and then cross the event horizon at a roughly parallel angle. This parallel movement resembles water draining down a funnel, the water doesn't simply fall in, it swirls in a downward spiral.

If the star crosses in a parallel fashion, then it would start by just the outer edge of the star crossing the horizon while the bulk of the star's weight would not be close enough to the singularity for its light to become 'trapped', thus the bulk of the star would continue to use its orbital momentum to propel itself around the singularity at a high enough velocity that centrifugal force would allow this portion of the star to continue to emit information (light, rays) that we can detect.

Perhaps someone who actually knows physics can provide a more solid explanation, but that's my thinking.

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This is right. It does not get sucked in as a "whole" per se. Think of it as Vacuum sucking up a ball of sand. It does not instantly get sucked up, but the stuff closest goes first, followed by what's behind it.. etc etc.

Plus, as the planet gets sucked in, the rest of the planet becomes less dense and heavy, and therefore gets more sucked in. Kind of hard to explain, but basicly F= G m1m2/r2

where f= force between masses, g = gravity constant (big number) m1 and m2 are the masses of the star and the blackhole, and r is the distance between them..

So in short, the planet gets sucked in slowly like a vacuum sucking up sand. What viking said was mostly correct, as the gravitational force between them is not strong enough to suck the whole planet in instantly, but slowly eating it up until it finally swallows the rest of planet

source;physics classes

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yeah my bad. meant star. i'm still pretty confused how they saw it. usually, light doesn't get a chance to escape so scientists have an incredibly hard time to see blackholes (usually they just see a void where planets/stars used to be). interesting stuff.. space, man.

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Actually, gmm/r^2 doesn't work well near a black hole. You have to go to general relativity to get the right answers. G(u,v)=8*pi*T(u,v)

The reason the star gets ripped apart is because it enters an orbit around the black hole. You can see at the start of the video that the star "misses" the black hole (as it pretty much always does). It then gets whipped around really quickly and falls apart because it is a big ball of gas.

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