Black hole extravaganza from ESOcast. Not long ago, watching something being ripped apart as it falls towards a giant black hole would be science fiction. This is now reality.
Observers under dark skies, far from the bright city lights, can marvel at the splendor of the Milky Way, arching in an imposing band across the sky. Zooming in towards the center of our galaxy, about 25000 light years away, you can see that it is composed of myriads of stars.
This is a pretty impressive sight, but much is hidden from view by interstellar dust, and astronomers need to look using a different wavelength, the infrared, that can penetrate the dust clouds. With large telescopes, astronomers can then see in detail the swarm of stars circling the supermassive black hole, in the same way that the Earth orbits the Sun.
The Galactic Center harbors the closest supermassive black hole known, and the one that is also the largest in terms of its angular diameter on the sky, making it the best choice for a detailed study of black holes.
This black hole’s mass is a hefty four million times that of the Sun, earning it the title of supermassive black hole. Although it is huge, this black hole is currently supplied with little material and is not shining brightly. But this is about to change.
Using ESO’s Very Large Telescope, a team of astronomers has discovered a new object that is heading almost straight towards the black hole at vertiginous speed. The object is not a star, but a cloud of gas.
“The cloud consists mainly of hydrogen gas, gas which we see anyhow in the galactic center all over the place. This particular cloud weighs more or less three times the mass of Earth. So it’s a rather small and tiny blob only, but it glows very brightly in the light of the stars which are surrounding it .”
As the astronomers watch, the cloud has been picking up pace as it gets closer to the giant black hole. Its speed has doubled in the last seven years and it is now speeding towards the black hole at more than 8 million kilometers per hour.
The astronomers have already seen the cloud’s outer layers becoming more and more disrupted over the last few years as it approaches the black hole. But the exciting part is yet to come.
“The Black hole, imagine it sitting here, has a tremendous gravitational force and the cloud, as it comes in, it will be elongated and stretched, it will become essentially like spaghetti. It will be elongated and falling into the black hole.”
“The next few years will be really fantastic and exciting because we are probing the territory. Here this cloud comes and gets disrupted, but now it will begin to interact with the hot gas right around the black hole. We have never seen this before.”
No one knows what will happen next. The cloud will probably heat up and may start to emit powerful X- rays as it gets disrupted. In the end the material will eventually disappear by falling into the black hole. For the scientists, this event is truly a unique chance to probe the hot gas around the black hole.
“But this process of how material gets into the black hole really is not clear to us we don’t understand it in any detail. And here in the galactic center we have an opportunity so to speak to have a probe of this process. How material really gets added to the black hole, and what the physical processes are, how the interactions happen in this very central region. That’s a fantastic opportunity.”
This is indeed science fiction becoming science fact.
