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Chandra Sees Black Hole Rip Star Apart
beeplet writes "Nasa just sent out this press release titled about an exciting Chandra observation. It states: "Thanks to two orbiting X-ray observatories, astronomers have the first strong evidence of a supermassive black hole ripping apart a star and consuming a portion of it.
The event, captured by NASA's Chandra and ESA's XMM-Newton X-ray Observatories, had long been predicted by theory, but never confirmed."
There is more information on the Chandra home page, including the x-ray and optical observations that were involved in the discovery." Note that the star-ripping pictured on the front page is labeled an illustration, rather than an recorded image.
I know Stefanie a little bit (overlapped at some meetings). This is her second coup in the last year -- she was also involved with using X-ray observations to identify a binary black hole in another active galaxy. There has been good evidence for such X-ray flaring in the past from ROSAT data alone (now you see it, now you don't), but this is the first time to catch one of these things in the act using XMM and Chandra which are much more capable than the previous generation of X-ray telescopes. XMM can collect more photons, and Chandra can provide image quality equal to that of optical telescopes (telescopes like ROSAT were 100 times worse). We still have no idea how important such stellar disruptions are in the grand scheme of thing, fuelling black holes, etc., but dang, they are cool. I want to put one in a science fiction novel someday.
Professor of Astronomy, Author of Spider Star & Star Dragon (Tor)
Any evidence of gravity waves from this? If "gravity waves" do travel at C, this is a good way to see them.
Or do we have to be outside the solar system to observe them?
Physicists at may soon be manufacturing copious quantities of black holes. When the Large Hadron Collider (LHC) at CERN, the European particle physics laboratory near Geneva, is completed in 2005, it could produce a black hole every second.
These tiny, fleeting phenomena might just give researchers a long-sought glimpse of the hidden dimensions of space.
This development of Black Holes on the planet poses big questions about the dangers and risks involved in handling Black Holes. If one gets out of control, it could potentially "eat" through our planet in no time.
This story has been getting a lot of attention on other time-travel/astronomy related sites, supposedly because people think it was predicted by a time traveller (do a google search). Just some food for thought.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
To answer those questions, you have to first understand what it is that a black hole is. It isn't some magical thing that eats whatever it touches. It doesn't have infinitely strong gravity.
It's just a normal piece of matter like any other. The only difference is that a black hole is dense enough that it can catch light.
Now, as you approach a black hole, time dialation increases and the apparent event horizon of the black hole decreases. Once you hit the Schwarzchild Radius, there is no escape because there's an infinite red shift on anything moving outwards. However, for you, time would still be passing.
Black holes cause gravitational distortions sort of like shear forces on a bolt. These shear forces can break matter apart quite effectively. If the black hole is small (like a thin metal plate pushing on the bolt), then it might tear a hole in the matter. If the black hole is big (like a REALLY THICK metal plate), it will still eventually tear you apart, but much more regularly. Really, that second case is analogous to pushing a bolt into a block of metal sideways. The force is fairly even all over the bolt.
Another problem with the time dialation is that a small enough black hole (with an event horizon say, the size of a pea) would cause things to age differently. Put it near a plate of steel and the steel closest to it would age significantly more slowly than the steel at the edge of the plate.
To answer your first question, if a black hole was coming to devour us, it would take quite a while as percieved by us, the devoured. The second question is quite different. We would certainly be able to notice a black hole coming to devour us. X-Rays would probably be the best indicator, since black holes are quite powerful X-Ray sources.
And last, the third question. I don't really know. With a planet-sized or smaller black hole, I would expect the Earth to tear itself apart as the rotational inertia of the side away from the black hole would cause great internal stresses on the Earth. With a large enough black hole, it probably wouldn't be too noticible at all for quite a while. Again, internal stresses would eventually break the Earth apart. However, that would have to be one FREAKISHLY huge black hole. We're talking larger than most stars, here. If the black hole is tiny, it would rip a hole through things, but the Earth might remain intact. It all depends on mass.
If I'm wrong here, somebody please correct me.
As I said in another reply, the X-rays are emitted from superhot gas spiraling around the black hole. Your description of the Hawking radiation theory is (mostly) correct, however. Virtual particles are constantly created/annihilated all throughout space, not just near black holes.
It is. Anyone who hasn't seen the movies of stars orbiting around the (presumed) black hole (3 million solar masses in a tiny volume) at the centre of our own galaxy should go here or here right now.
What would happen if two black holes came into close proximity of each other? I don't have enough knowledge about black holes to hypothesize, maybe some of you guys with more background on the subject could shed some light?
If you want the details, we had compiled apache for up to 2048 clients, but had left maxclients set to a meager 512, which caused some problems up until about 7pm eastern, when I bumped maxclients to 1536, and watched as actual connections peaked up around 900. We also had an errant script that was "gracefully" restarting the web server every 15 minutes, which boosted the load up to around 20 (the server actually didn't seem to mind). Fixed that quick.
The server, by the way is a SunFire 280R (dual 750 MHz) with 4G memory, attached by 100Mbit ethernet (from us to Harvard is gigabit, and from Harvard to the world is something really big). Once the errant script was stopped, load was steady around 1.9 (and I now also realize that there was an incremental backup in progress since about 6pm).
To paraphrase Kirk:
"I'm laughing at your superior network."