A giant black hole has been caught with its hand in the proverbial cookie jar, in the earliest stages of ripping apart and consuming a star.
On 28 March, NASA's Swift telescope detected several bright bursts of X-rays coming from a patch of the sky where no X-rays had been detected before.
Now two teams, one led by David Burrows of Pennsylvania State University in University Park and the other by Ashley Zauderer of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, say the bursts were probably chunks of a star that was dismembered when it wandered too close to a black hole located 4.5 billion light years away.
Since the star was orbiting the black hole before it was ripped apart, its remains continue to swirl around the hole, which weighs a million suns, as they gradually get swallowed up. This "chewing" had been predicted theoretically and has possibly been seen around other black holes in the past.
The new observations now show that some of the star's remains were spewed out in a jet at 99.5 per cent the speed of light. Swift just happened to be lying directly in the jet's path, so it was able to make the first ever measurements of such a jet switching on.
The jet is narrow, says Burrows: "If it happens to be pointed at you, you see it, but if not, you miss it." Tracking how long the jet persists could reveal the stellar victim's mass and its original orbital distance, he adds.
"We think we're still seeing emission from the jet," Burrows says. "It probably takes at least months for the star to finish getting swallowed up in the black hole."
source: newscientistvideo
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