Slashdot Mirror
Astronomers Find Gas Cloud About To Fall Into Black Hole
First time accepted submitter pigrabbitbear writes "Black holes are basically celestial Cookie Monsters, gobbling anything and everything in sight. But because that appetite includes light itself, it's incredibly rare for us to actually see a black hole suck back an interstellar treat. Astronomers using the European Southern Observatory's Very Large Telescope have found just that: a mysterious, giant gas cloud that's rapidly been pulled into the maw of a supermassive black hole. The researchers, led by Reinhard Genzel of the Max-Planck Institute for Extraterrestrial Physics in Germany, discovered the cloud as part of a now 20-year ESO program tasked with tracking stars as they whirl around the supermassive black hole, known as Sgr A*, at the center of our galaxy."
That's actually what the article says.
Correction: This already happened 27,000 years ago. We're just getting a look at it now.
Isn't it possible that the gravitational field of a black hole would also cause some "masses" to rotate around it like a sun or does it just suck everything in?
Yes-one of the confirmations of our own galaxy's central black hole was the observation of 3 (I think) stars, whizzing around an "invisible" object at break-neck speeds.
So what does "about to" mean in astronomical terms? Tomorrow? Next year? In a few million years?
Roughly two years: http://www.scientificamerican.com/article.cfm?id=black-hole-gas-blob
thegodmovie.com - watch it
But also 25,900 ± 1,400 years ago.
I am a free slashdotter. I will not be modded, blogged, DRM'd, patented, podcasted or RFID'd. My life is my own.
But I don't expect that many black holes would be big enough as to irradiate an entire galaxy to the point that life is impossible anywhere in that galaxy.
However, the very brightest celestial objects that we can see are the Quasars, or Quasi-Stellar objects. They are "Stellar" in that they appear to be pinpoint light sources, but their spectrum is heavily weighted to the bluer, higher energy end of the spectrum, and if I understand correctly do not appear to be radiating light as a result of just being hot. When an object emits thermal radiation, while that radiation is blueer (or 'X-ray-er') if it is particularly hot, the shape of the spectral intensity distribution takes an easily calculated form called the Planck Distribution.
There are lots of other ways to generate blue light other than thermally, but for many years, the incredible power of the Quasars was a mystery. The red shift of their spectrum that results from the expansion of the Universe between us and them is quite large, so clearly they are the farthest objects we can see, as well as the oldest, and must have formed not long after the beginning of the Universe.
It is thought now that the Quasars are very large black holes, such as those at the centers of some galaxies such as our own, but much much larger. I expect life would not be possible anywhere in their vicinity.
If a supernova goes off in any nearby galaxy, we can easily resolve it from its neighboring stars with average sized astronomical telescopes. Supernovas in more distant galaxies cannot be resolved, but they are at times as bright as the entire galaxy that they are contained within. If a supernova goes off within our own galaxy, at times we can easily see it at high noon on a bright, sunny day.
If any of our nearby celestial neighbors were to go off in a supernova, we would only get the bad news when all life on earth was wiped out almost instantly. We wouldn't just get 73h c4nc3r and die a few years later; the Earth's entire atmosphere would be blasted off into interstellar space.
The abundance of heavy elements not just on earth but throughout our solar systems makes us certain that the Sun is a second generation star, whose first generation star went off in a supernova, the intense pressure, heat and particle energy of which formed all those heavy elements that we find so useful for things like hard drive platters and Liquid Crystal Displays.
Request your free CD of my piano music.
What makes the approach to a black hole dangerous is not the intense gravity, but the very high gradient of that gravity. That is, if you were falling headfirst into a small black hole, your head would be accellerated inward faster than your feet, as if you were on a medieval stretching rack. If you were falling into a large black hole, while your head would still be accellerated more than your feet, the structure of your body would be strong enough to resist any injury.
Request your free CD of my piano music.