English subtitles for clip: File:A Black Hole’s Dinner is Fast Approaching - Part 2.ogv

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Not long ago, actually watching something being ripped apart 

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As it falls towards a giant black hole would be science fiction. 

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But this is becoming reality

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for astronomers using ESO's very large telescope. 

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We will see how science fiction has turned into science fact, 

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as astronomers observe the progressive destruction 

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of a cloud of gas that’s being pulled in by a supermassive black hole. 

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ESO telescopes have been used to track the motion of stars 

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around a giant black hole at the center of our galaxy for 20 years. 

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This black hole’s mass is a hefty 4 million times that of the sun, 

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earning it the title of supermassive black hole. 

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Although it is huge, this black hole is currently supplied with little material, 

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and is not shining brightly, but this is about to change.

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Using ESO’s very large telescope, 

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a team of astronomers has discovered a new object that is heading almost straight towards the black hole 

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at vertiginous speed. The object is not a star, but a cloud of gas.

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The cloud consists mainly of hydrogen gas, 

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gas which we see any how in the galactic center all over the place. 

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This particular cloud weighs more or less 3 times the mass of Earth, 

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so it’s a rather small and tiny blob only. 

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But it glows very brightly in the light of the stars which are surrounding the cloud. 

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As the astronomers watched, 

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the cloud has been picking up pace as it gets closer to the giant black hole. 

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Its speed has doubled in the last 7 years, 

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and it is now speeding towards the black hole at more than 8 million km/h. 

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The astronomers have already seen the cloud’s outer layers becoming more and more disrupted 

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over the last few years as it approaches the black hole. 

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But the exciting part is yet to come.

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The black hole, imagine it sitting here, 

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has a tremendous gravitational force, and the cloud, 

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as it comes in, it will be elongated and stretched. 

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It will become essentially like spaghetti. 

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It will be elongated and falling into the black hole. 

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Well the next few years will be really fantastic and exciting 

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because we are probing the territory. Yeah, this cloud comes in gets disrupted, 

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but now it will begin to interact with the hot gas 

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right around the black hole. We have never seen this before. 

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No one knows what will happen next. 

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The cloud will probably heat up and may start to emit powerful x-rays as it gets disrupted. 

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In the end, the material will eventually disappear by falling into the black hole. 

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For the scientists, this event is truly a unique chance 

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to probe the hot gas around the black hole.

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But this process of how material gets into a black hole is really is not clear to us, 

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we don’t understand it in any detail. And here, in the galactic center, 

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we have an opportunity, so to speak, to have a probe of this process. 

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How material really gets added to the black hole, and what the physical processes are, 

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how the interactions happen in this very central region. 

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That’s a fantastic opportunity. 

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This is indeed science fiction becoming science fact.