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Astronomers Discover 33 Pairs of Waltzing Black Holes
Astronomers from UC Berkeley have identified 33 pairs of waltzing black holes, closing the gap somewhat between the observed population of super-massive black hole pairs and what had been predicted by theory. "Astronomical observations have shown that 1) nearly every galaxy has a central super-massive black hole (with a mass of a million to a billion times the mass of the Sun), and 2) galaxies commonly collide and merge to form new, more massive galaxies. As a consequence of these two observations, a merger between two galaxies should bring two super-massive black holes to the new, more massive galaxy formed from the merger. The two black holes gradually in-spiral toward the center of this galaxy, engaging in a gravitational tug-of-war with the surrounding stars. The result is a black hole dance, choreographed by Newton himself. Such a dance is expected to occur in our own Milky Way Galaxy in about 3 billion years, when it collides with the Andromeda Galaxy."
Apparently, the definition "waltzing"/a waltz has been diminished to the extent that now it just refers to two objects moving together. Hum.
I guess I'm just a cranky music theory lover though.
Who leads and who follows?
http://en.wikipedia.org/wiki/First_Amendment_to_the_United_States_Constitution
the Y3B bug already being dismissed as irrelevant
At those masses, the choreographer is most likely Einstein (nvm that dark matter might be not the underlying cause of some discrepancy between how we think gravity works and what we are observing at galactic scales; we might as well have a different choreographer yet)
One that hath name thou can not otter
Wake me up when they've found some doing the Foxtrot or the Lindy Hop.
"[...] a merger between two galaxies should bring two super-massive black holes to the new, more massive galaxy formed from the merger. The two black holes gradually in-spiral toward the center of this galaxy, engaging in a gravitational tug-of-war with the surrounding stars. The result is a black hole dance, choreographed by Newton himself. Such a dance is expected to occur in our own Milky Way Galaxy in about 3 billion years, when it collides with the Andromeda Galaxy."
Don't worry - I'm sure Russia will have an ill-defined plan to divert this somehow. By then.
(Sorry, couldn't resist.)
be square dancing?
... is the only "Dancing with the Stars" I'd ever want to see.
Finally I can post this link and not be offtopic:
http://www.youtube.com/watch?v=Cg1dMpu4v7M
Knowledge is power. Knowledge shared is power lost.
choreographed by Newton himself.
He might try, but the accurate calculation of black hole orbits requires the complete infrastructure of General Relativity, so Einstein is calling this tune.
Wow, when I was in university, Black Holes were still a mostly theoretical idea and we had no real empirical evidence to support their existence.
Now we've got 33 pairs of them entwined in death spirals, and we're pretty sure every galaxy has one.
There's still a lot out there that we can't even conceive of ... I can't wait to see what the next 15-20 years brings us. I like the fact that the universe is vastly more complicated than we've ever really been able to guess at.
Cheers
Lost at C:>. Found at C.
Great, the collision of these things is exactly the kind of event we need for detecting gravitational waves. These kind of 'inspirals' emit very distinct pattern, which can be retrieved very efficiently from the noise with matched filter banks. The higher the mass, the lower the frequency of this 'chirped' signal, so it is probable that these colliding super-massive black-holes cannot be detected with the ground-based kilometer long observatories, which are measuring right now. This is probably more something for the space-based LISA mission, which can probe much lower frequencies since it has a base-line of millions of kilometers.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]
Given that it's pretty common knowledge that a) galaxies have big black holes at their centers and b) that galaxies collide... is it really a discovery that black holes will orbit one another as their gravity catches hold of one another?
I mean okay, it's cool to actually have proof of it but I am pretty sure I read about orbiting black holes a while back already. Not to take the icing off the cake here, I am probably more annoyed with the slashdot heading.
Moved to http://soylentnews.org/. You are invited to join us too!
1) How long does it take two such objects to coalesce? Are we talking millions, billions, or trillions of years?
2) My memory is foggy, but ISTR that a black hole merger results in a significant fraction (10-20%) of the black holes' masses being released as energy.
That sort of energy release is in gamma-ray-burst territory when you're talking about stellar-mass black holes, but downright awesome when you're talking about the potential for a merger between two supermassive black holes.
So if a single magnestar can produce a truly massive gamma ray blast just by displacing its crust by a couple of centimeters http://science.slashdot.org/story/09/12/27/1639207/Fifth-Anniversary-of-a-Cosmic-Onslaught, what happens when two super-massive black holes finally merge?
Okay, great. Exciting observations, but really, not that useful in the big scheme of where we are with physics today.
How about you physicists show us Higgs? How do quantum mechanics and gravity mesh into a coherent theory? Explain the disagreement of 107 orders of magnitude (yes, you read that right: 107 zeros) between the upper bound upon the vacuum energy density (from data obtained from Voyager, less than 10**14 GeV/m3) and the zero-point energy of 10**121 GeV/m3 - calculated using quantum field theory, or alternately: Why doesn't the zero-point energy of the vacuum cause a large cosmological constant? Why is there far more matter than antimatter? Are protons stable - if not, what's the half life? Is SUSY real or just implied? What governs the transition of quarks and gluons into pions (ie explain QCD)? What's the mass of a Neutrino? Explain why the fundamental physical constants have the exact and seemingly arbitrary yet interconnected values they have? Why did the universe have such low entropy in the past? What causes gamma ray bursts? and on and on and on...
But most of all, explain what causes the observed effects of hypothetical "dark matter" and "dark energy". My young children are smart enough to know that the dark matter story sounds like total and utter bull. The story goes like this: "We see something that looks like it causes things to move, but we don't know what it is, and we can't see it, or measure it, create it, or understand it at all. These unobservable matter blobs (and energy) may be 95% of everything we observe! We see something we can't explain, so we're calling it 'dark matter' and moving on with the old story that has worked for a while and still gets us grant funding." Why no one with a brain is calling out this story for its absurdity is astounding.
These issues are not subtle or small. The theories science (specifically physics) now promotes and teaches about the physical world, while highly accurate and highly reproducible in different areas, are *impossibly inconsistent* and *abundantly incomplete*. For science, inconsistency on this scale is a crisis requiring a revolution in thought.
The most dangerous hubris in science is the refusal to accept that we're far more ignorant about our physical environment than most would like to admit.
Funny how everybody is always talking about all those black holes in the universe while, in fact, none currently exist. Sure, there are objects that are very, very close to becoming a black hole, and for all practical intents and purposes they can be pretty much considered as such, but in our reference frame it will still take an infinite amount of time before that last bit of matter falling in makes it an actual black hole, with event horizon and all. That's because the intense field of gravity slows down time to an asymptotic halt, so the approaching last bit of matter required for the true black hole will pretty much stop before it gets far enough (from our point of view). The only person who will ever be able to say that black holes exist, is someone who is actually falling into one (which, from an outside observer's point of view, would take an infinite amount of time even though the person himself will experience the event in finite time).
As with so much of science: if you went out there and didn't find it, that would be much bigger news, because it would cast doubt on your present theory.
Confirmation is never as exciting as falsification, but it's good that science isn't all that exciting, or nothing would ever get done. The more confirmations you get, the further you can speculate, with the chance of getting something that can be falsified.
The classical google portal has an interesting Newton animation.
For the holidays, isn't it. If they only did it before Christmas...
Well, as it's theorized the Milkyway has already swallowed others (reference missing), there should either be multiple black holes in our galaxy, or this provides a good estimation of how long it's been since that happened -- according to Einstein, of course.
âoeThe wall between art and engineering exists only in our minds.â -- Theo Jansen
Such a dance is expected to occur in our own Milky Way Galaxy in about 3 billion years, when it collides with the Andromeda Galaxy.
I'll believe that when I see it...
You have the right to remain sentient. If you give up the right to remain sentient, you will be elected to public office
This is all caused by global warming :P
3 billion years for a species to not kill itself long enough to escape this galaxy, lest all life on it perish?
From TFA:
>The dual supermassive black hole pairs can in turn
>be used to estimate how often galaxies merge, and
>the team concludes that red galaxies from between 4
>and 7 billions years ago underwent 3 mergers every
>billion years.
Unless I'm not understanding something, that would mean that in the 3 billion year period (between 4 and 7 bya), the subject galaxies experienced an average of 9 mergers. If each merger results in two galaxies merging into one, then that means there were more than 500 times fewer galaxies (2^9) 4bya than 7bya
That's pretty dramatic, is there anything wrong with my math?
1) nearly every galaxy has a central super-massive black hole 2) galaxies commonly collide and merge to form new, more massive galaxies. [...] The two black holes gradually in-spiral toward the center of this galaxy, engaging in a gravitational tug-of-war with the surrounding stars.
If this was a comment on the life of corporations, I would mod it "Insightful" (just substitue "galaxy" with "corporation" and "back hole" with "CEO").
Just goes to show you, micro and macro-scale ecology is eeringly similar. I think we need a lecture on fractals and how they apply to this situation.
Get two very hungry black hole together, can one eat up another?
Very very long indeed. I understand the timescales in TFA are in million to billion years, so the frequencies photonic expects to detect would be conversely so low that this'll just be a constant at our timescale... I fear we'll not see a turn ;-)
Herve S.
When the galaxies collide , what effect does it have on the inhabiting planets inside that galaxy, or is it something you would not feel, just all of a sudden (like in a crowded gym...) you look up to see twice as many people (or in this case planets and stars) then before?
If your detector is sensitive enough to observe lots of galaxies at the same time, you will be able to observe a few at the final stage of the inspiral. The system looses energy due to gravitational waves, thus the distance between the two objects will decrease and the rotation frequency will increase up to the point that they merge. It is this final stage that we want to detect, which the gravitational waves are sent with higher frequency and intensity.
karma police: arrest this man, he talks in maths; he buzzes like a fridge, he's like a detuned radio. [radiohead]