Posted on 04/30/2008 8:00:18 AM PDT by RightWhale
Garching, Germany (SPX) Apr 30, 2008
By an enormous burst of gravitational waves that accompanies the merger of two black holes the newly formed black hole was ejected from its galaxy. This extreme ejection event, which had been predicted by theorists, has now been observed in nature for the first time. The team led by Stefanie Komossa from the Max Planck Institute for extraterrestrial Physics (MPE) thereby opened a new window into observational astrophysics. The discovery will have far-reaching consequences for our understanding of galaxy formation and evolution in the early Universe, and also provides observational confirmation of a key prediction from the General Theory of Relativity (Astrophysical Journal Letters, May 10, 2008). When two black holes merge, waves of gravitational radiation ripple outward through the galaxy at the speed of light. Because the waves are emitted mainly in one direction, the black hole itself is pushed in the opposite direction, much like the recoil that accompanies the firing of a rifle or the launching of a rocket. The black hole is booted from its normal location in the nucleus of the galaxy. If the kick velocity is high enough, the black hole can escape the galaxy completely.
The MPE team's discovery verifies, for the first time, that these extreme events actually occur; up to now they had only been simulated in supercomputers. The recoiling black hole caught the astrophysicists' attention by its high speed - 2650 km/s - which was measured via the broad emission lines of gas around the black hole. At this speed, one could travel from New York to Los Angeles in just under two seconds. Because of the tremendous power of the recoil the black hole, which has a mass of several 100 millions solar masses, was catapulted from the core of its parent galaxy.
In addition to the emission lines from gas bound to the recoiling black hole, the astronomers were also struck by a remarkably narrow set of emission lines originating from gas left behind in the galaxy. This gas has been excited by radiation from the recoiling black hole. Gas that moves with the black hole - the so-called accretion disk gas - continues to "feed" the recoiling black hole for millions of years. In the process of being accreted, this gas shines in X-rays.
In fact the team around Komossa also detected this X-ray emission from the disk around the black hole at a distance of 10 billion light years: by chance the region was scanned by the satellite ROSAT, and at the extreme end of the visual field an X-ray source was discovered the position of which corresponds with the distant galaxy.
The new discovery is also important because it indirectly proves that black holes do in fact merge and that the mergers are sometimes accompanied by large kicks. This process had been postulated by theory, but never before confirmed via direct observation. Another implication of the discovery is that there must be galaxies without black holes in their nuclei - as well as black holes which float forever in space between the galaxies.
This raises new questions for the scientists: Did galaxies and black holes form and evolve jointly in the early Universe? Or was there a population of galaxies which had been deprived of their central black holes? And if so, how was the evolution of these galaxies different from that of galaxies that retained their black holes?
In a close interplay between theory and observation, the astrophysicists prepare to answer these questions. Various detectors on earth and in space, for example the space interferometer LISA, will be set on the track of gravitational waves. The discovery of the MPE team will provide new impetus for theorists to develop more detailed models of the superkicks and their consequences for the evolution of black holes and galaxies.
That is... several hundred MILLION solar masses.
Sounds like Reverend Wright on the can after downing a burrito
Yup, amen to that, brother (and this thread wouldn’t have been relegated to the black hole of all forums either!).
Nice article, thanks.
Spin it up and it works just great. Now, sick a big ol' wad of bubblegum to it maybe 1/4 the way to the top.
When you spin it up to its highest speed it'll look pretty good, but there's going to be a wobble ~ not much at first, but as it slows down the wobble becomes worse and finally the top and the gum if still attached, will skid off it's axis and fly wildly away.
Two black holes merging is like sticking bubble gum on the neighbor kid's top.
An isolated black hole can simply mean that it has already consumed all or most of the matter surrounding it.
Black holes are believed to exist on various scales. There are stellar black holes (remnants of super nova star explosions) and there are huge galactic black holes at the center of galaxies with masses millions or billions times that of our sun. The existence of black holes is basically determined by the behavior of visible material surrounding it. And by 'visible' this might mean in various other frequencies of the light spectrum (infrared, x-ray, gamma rays, etc).
That’s true, but you can see the effect it has on any matter that’s close to it but not yet over the event horizon.
Similar to modern human society, the parents kick the kids out but the kids continue to sponge off them for food, gas, etc.
For the analogy to hold, you would have had to, er .... mated with another @$$hole....
Is there something you're trying to tell us? ;-)
While it would gobble what it passed close to upon entering a galaxy at 9.5 million kph, it would also gravatationaly leave a very interesting wake in such a punch-through.
I imagine we could re-examine some interesting galactic and cluster shapes with this sort of wild cue ball in mind.
Now there’s a PhD thesis for somebody... Work out, or predict, how a supermassive black hole would perturb stars in galaxy as it passed through, then, icing on the cake, go to the telescope and find evidence confirming it.
...perturb stars in A galaxy...
The relative closing speed, based upon the movement for the galaxy itself might make the disturbance larger or smaller. Add in the angles of passage and you have some neat disturbances unless you happen to be on a nearby inhabited planet.
If the later was the case we would be at a “great distrubance in the Force” moment for sure.
Just wondering when you came to the realization that you were an @$$hole at 18.
I am wondering when my stepson may come to accept that fact about himself.
Just recently, right after I turned 50.
Errr.... come to think of it...
If the universe has an edge, then what's on the other side of that edge?
On a more depressing note his younger sister is even more so!
I’ve got a 20 going on 21 I could kill.
But you know what really got me? My 17 year old. He is the nicest, sweetest, most considerate and grateful kid you could ever meet.
Really highlighted for me what an @$$hole I was when I was his age.
If the universe has an edge, then what's on the other side of that edge?
The universe might not have an 'edge', but the *observable* universe definitely does, because it's simply the limit to which we can see (in every direction). Regions of space beyond this limit are moving away faster than light and so are impossible to perceive.
More info here:
http://en.wikipedia.org/wiki/Observable_universe
Added to my backlog of over 600 articles to read...
Cheers!
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