Saturday, June 18, 2011

Star gets eaten up by black hole

When I consider thy heavens, the work of thy fingers, the moon and the stars, which thou hast ordained;
What is man, that thou art mindful of him? and the son of man, that thou visitest him?
Psalms 8:3-4

The heavens declare the glory of God; and the firmament showeth his handiwork. Psalms 19:1

Thou art worthy, O Lord, to receive glory and honour and power: for thou hast created all things, and for thy pleasure they are and were created. Revelation 4:11

As reported by Margaret Munro of Postmedia News on June 16, 2011:

In late March, NASA's Swift satellite picked up a blast of gamma rays screaming past Earth.

Astronomers rushed to take a closer look, using powerful telescopes from Hawaii to the Canary Islands to check out the high-energy jet coming from a distant galaxy in the constellation Draco.

They initially speculated a collapsing star created the blast. Now they report that it appears a star the size of the sun was shredded by a massive black hole. Its "death rattle" was a high-energy flash or jet pointed straight at the Earth.

"This is a very strange one," says Nicholas Law, at the University of Toronto's Dunlap Institute for Astronomy and Astrophysics, a member of the international team that describes the cosmic drama in two reports published Thursday by the journal Science.

NASA's Swift satellite is designed to pick up brief, intense flashes of gamma radiation. The blasts can come from any direction in the sky and typically last from a few milliseconds to minutes.

After detecting the burst March 28, Swift alerted ground dates and a bulletin went out to astronomers, who focused everything from the Gemini North telescope in Hawaii to the Hubble Space Telescope on the unusually bright and long-lasting emissions from a galaxy nearly 4 billion light years away...

..."This is truly different from any explosive event we have seen before," Joshua Bloom, of the University of California Berkeley, says in a release. Bloom is lead author of one of the Science reports.

It was one of the biggest and brightest bangs yet recorded, the scientists say, and the evidence indicates it came from a massive black hole at the centre of the distant galaxy. They say the high-energy X-rays and gamma rays persisted at an extremely bright level for weeks, with flares when chunks of the star fell into the black hole.

"This burst produced a tremendous amount of energy over a fairly long period of time, and the event is still going on more than 2 1/2 months later," says Bloom. "That's because as the black hole rips the star apart, the mass swirls around like water going down a drain, and this swirling process releases a lot of energy."

It's estimated that about 10 per cent of the star's mass turned into energy generating the beam or jet of X-rays and gamma rays. Earth just happened to be in its path. "We're looking down the barrel," says Bloom.

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