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Two Supermassive Black Holes About To Embrace

samzenpus posted about 5 months ago | from the old-BOB-approved dept.

Space 171

Taco Cowboy writes "NASA's WISE (Wide-field Infrared Survey Explorer) satellite was looking at a distant galaxy, some 3.8 billion light-years away, and saw something rather unusual. At first they thought that they saw a galaxy was forming new stars at a furious rate, but upon closer checking, they found that they were seeing two supermassive black holes spiraling closer and closer to each other. The dance of this black hole duo started out slowly, with the objects circling each other at a distance of about a few thousand light-years. As the black holes continued to spiral in toward each other, they were separated by just a few light-years. Supermassive black holes at the cores of galaxies typically shoot out pencil-straight jets, but in this case, the jet showed a zig-zag pattern. According to the scientists, a second massive black hole could, in essence, be pushing its weight around to change the shape of the other black hole's jet. Visible-light spectral data from the Gemini South telescope in Chile showed similar signs of abnormalities, thought to be the result of one black hole causing disk material surrounding the other black hole to clump. Together, these and other signs point to what is probably a fairly close-knit set of circling black holes, though the scientists can't say for sure how much distance separates them."

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171 comments

FSVO "about" (1, Insightful)

Anonymous Coward | about 5 months ago | (#45614829)

I'm not sure you can use the term "about" to describe something that happened 3.8 billion years ago

Re:FSVO "about" (1)

Dunbal (464142) | about 5 months ago | (#45614909)

You're right - they probably already have!

Re:FSVO "about" (-1)

Anonymous Coward | about 5 months ago | (#45615329)

Watching Deep Space Nine and something ocured to me. You know why the Star Trek world doesnt really have any racism between Humans? Because it doesn't have any thug gangstas. Is that so hard to understand??? All the violent crime and drug abuse and women abuse and broken families make every racist white people feel justified. Is that so hard to admit?? I can go thru the rural areas where white people live and not worry about gettin shot by some gangbanger because i look up and make incidental eye contact. Fix that shit in the black community and white racism will disappear. See the connection? If this was a computer program you would see the causation and think it is obvious. This subject is so special you cannot do the same?

Re:FSVO "about" (-1)

Anonymous Coward | about 5 months ago | (#45616529)

They still have Jews, though they're called Ferengi.

Re:FSVO "about" (5, Interesting)

Opportunist (166417) | about 5 months ago | (#45615127)

Did it really? I think that's a philosophical question. Personally, I think not only space and time but also cause and effect are relative to the spectator.

The light carrying the information that this is happening is just arriving here. The speed of light is also by definition the fastest information can travel. It may "in reality" have happened 3.8b years ago, but the effect can only now affect someone here. Even if you happened to have an observation post there and 3.8b years ago they noticed "hey, they're falling into each other NOW", and they sent that information right away, the information would not have reached us before the event since, well, the information of the event ITSELF is traveling at the speed of light, which, as stated before, is the fastest an information sent to us by the observation post could have traveled.

Long story short, the absolute moment in time when something happens does not matter as long as you cannot overcome its information propagation speed. It will of course change if someone happens to find a way to propagate information faster than the speed of light... which would open a completely different can of worms if you ask me (but that's beyond the scope of this post now).

What this all comes down to is that the absolute moment of some event does not matter, but only the relative moment that you receive the information.

Re:FSVO "about" (-1)

Anonymous Coward | about 5 months ago | (#45615275)

The speed of light is also by definition the fastest information can travel.

No, it's not.

Re:FSVO "about" (4, Funny)

Sardaukar86 (850333) | about 5 months ago | (#45616085)

The speed of light is also by definition the fastest information can travel.

No, it's not.

Sorry, Opportunist, it looks like this eloquent and reasoned rebuttal has not only completely defeated your argument but also dealt a death blow to that silly Special Relativity baloney.

Re:FSVO "about" (3, Insightful)

digitig (1056110) | about 5 months ago | (#45617473)

It's not by definition the fastest information can travel. It's the fastest according to our current understanding, which might be wrong.. The OP confused a priori with a posteriori truth -- logical certainty with scientific confidence.

Re:FSVO "about" (0)

Anonymous Coward | about 5 months ago | (#45617997)

I think his full argument is: "No, its not. U R gay"

Re:FSVO "about" (1)

geminidomino (614729) | about 5 months ago | (#45615321)

That's rather solipsistic, isn't it?

Re:FSVO "about" (1)

Your.Master (1088569) | about 5 months ago | (#45616999)

Not necessarily, it's just relativistic. It's hard to break out of an absolutist mindset, but there isn't really a sensible way to say that the black hole is there at all without invoking a set of physics that outright demands you think relatively. Remember, we're actually observing phenomena which is consistent with a physics model that is rooted in relativity, not downloading absolute knowledge of the existence of black holes at this location in spacetime.

The entire population of earth is essentially in the same observation "moment" in time relative to this black hole, though.

Re:FSVO "about" (4, Informative)

CapOblivious2010 (1731402) | about 5 months ago | (#45615373)

You're close - but the whole point of relativity is that there is no "absolute time". With one caveat (see below) It's ALL relative to the observer. There are some observers (specifically those roughly motionless with respect to the earth and the two black holes, like us) for whom "then" and "now" are separated by 3.8b years. There are (or could be) other observers (specifically those traveling at something close to the speed of light in along a line between the black holes and us) for whom the two events are separated by far less time. For someone traveling along that line at the speed of light, the two events would be simultaneous.

The only hard and fast rule is that space-time is divided into 3 zones:
* The absolute past - events within (or on the surface of) the light-cone leading up to here-and-now
* The absolute future - events within (or on the surface of) the light-cone starting at here-and-now
* Everything else - events in neither light cone, which means they cannot affect us and we cannot affect them. Depending on an observer's motion relative to us and such an event, someone might see the event as happening at the same time as the here-and-now, or before, or after. It doesn't matter, because such an event is not causally connected to the here-and-now in either direction.

The interesting thing is that the vast majority of the universe is in the "everything else" zone.... contemplate that one for a while...

Re:FSVO "about" (0)

Anonymous Coward | about 5 months ago | (#45615831)

Even more interesting, the observable universe may in fact be almost infinitely small relative to the rest of the universe if inflation theory is correct.

Re:FSVO "about" (0)

Anonymous Coward | about 5 months ago | (#45616365)

Inflation theory doesn't say whether the universe is infinite or not, it is just potentially compatible with both an infinite and a finite universe.

Re:FSVO "about" (0)

Anonymous Coward | about 5 months ago | (#45616359)

You're close - but the whole point of relativity is that there is no "absolute time".

No, that's not true at all.

Re:FSVO "about" (1)

wonkey_monkey (2592601) | about 5 months ago | (#45616795)

Yes, it is.

(well, if you don't have to provide any evidence, nor do I).

Re:FSVO "about" (1)

Anonymous Coward | about 5 months ago | (#45618105)

Look, if he argues with you, he has to take a contrary position.

Re:FSVO "about" (1)

Your.Master (1088569) | about 5 months ago | (#45617023)

No, it's entirely true. Just look up the definition of relativity -- even just the word itself, not the physics term. It literally means the absence of absolutes -- in this case, space and time.

A consequence of relativity is that Alice and Bob can disagree on which came first: event C or event D, and both can be correct and both correctly think the other guy is incorrect, because each exists in a realm where their event actually did come first. Despite inhabiting the same universe.

This said, we think that C cannot cause D, nor D cause C, if there's any disagreement between Alice and Bob about which one came first. Only when one event precedes the other for all observers can the one possibly be the cause of the other.

Some of this gets trickier still when you look at some variations of the double slit experiment, eg. the delayed choice quantum eraser experiment, where an effect appears to precede a cause (alas, not in a way that lets us send a message to the past).

Re:FSVO "about" (0)

Anonymous Coward | about 5 months ago | (#45617951)

Just look up the definition of relativity -- even just the word itself, not the physics term. It literally means the absence of absolutes -- in this case, space and time.

Please don't encourage the etymological fallacy with jargon words. While it sucks so many fields will re-purpose common words for jargon, it relying on the common meaning for more exact answers related to jargon usage will get you in trouble. While it is true special and general relativity lack absolute time, the older Galilean relativity on the other hand includes absolute space and universal time.

Re:FSVO "about" (1)

ByteSlicer (735276) | about 5 months ago | (#45617363)

The interesting thing is that the vast majority of the universe is in the "everything else" zone.... contemplate that one for a while...

Hmm, I don't think this is correct, depending on what you mean exactly.

When we talk about the universe, we usually mean the observable universe. Since we receive light from all parts of the observable universe (it's observable after all), that means we are in the future light cones of those locations (each roughly an expanding sphere in 3D+time). If we can see something, it can effect us.

But, not all of those places are in our future light cone. Because of the metric expansion of space, which causes accelerated growth of the universe, our sun's light will never reach the outer regions of the observable universe, and we will never be able to travel there unless we find some way around the restrictions of general relativity (unlikely).

Re: FSVO "about" (1, Funny)

Anonymous Coward | about 5 months ago | (#45615417)

It does when your wife says she's three month pregnant, and you were on a business trip three months ago.

Re: FSVO "about" (1)

digitig (1056110) | about 5 months ago | (#45617489)

It does when your wife says she's three month pregnant, and you were on a business trip three months ago.

Good job she came with me, so I didn't have to calculate the relativistic effect of only one of us making the journey.

Re:FSVO "about" (1)

Galactic Dominator (944134) | about 5 months ago | (#45615727)

but also cause and effect are relative to the spectator

Well I suppose facts and science are relative to a spectator...at least until they try to replicate them.

Re:FSVO "about" (1)

cusco (717999) | about 5 months ago | (#45615869)

The speed of light is also by definition the fastest information can travel if that information is carried by light. If the information is carried by some other method, such as sound waves, then the speed of sound is the fastest it can travel. Remember, we can't even measure around 90 percent of the mass and energy in this universe yet. I would be very surprised if we don't eventually find something faster than light, at which point that will be your new speed limit.

Re:FSVO "about" (1)

Neil Boekend (1854906) | about 5 months ago | (#45616689)

Assuming that our current understanding of physics is correct, there is nothing that can travel beyond the speed of light through space-time.

That does leave us with some loopholes.
1. Our understanding of physics could be incomplete. There is much yet to discover, so this may be the case. However, the current models are verified extremely precisely.
2. Warp drives. Not traveling through space-time but morphing it would help. However this seems to require massive amounts of energy. I believe the last calculations said: about the mass of Jupiter.
3. Subspace. Not traveling through space-time but through something else would help. However we have no reason to believe there is a realm outside space-time, let alone get there, let alone survive there.
4. ...
5. Profit.

Re:FSVO "about" (1)

blue trane (110704) | about 5 months ago | (#45616949)

Regarding point 3 "we have no reason to believe...", that same argument was used against black holes once. From http://greekgeek.hubpages.com/hub/Real-Photos-of-Black-Holes [hubpages.com] :

Einstein himself thought they were "too strange to be real."

"When I was a PhD student, people used to giggle when you hear[d] about black holes. They're like unicorns, mythical creatures. We call this the 'giggle factor.' People would say, 'Beam me up, Scotty.' Well, no one is laughing anymore."

~ Dr. Michio Kaku, Theoretical Physicist, on How the Universe Works.

The relativity of wrong (1)

TapeCutter (624760) | about 5 months ago | (#45617919)

Yep, when I was at school black holes were considered a "mathematical curiosity", it was considered "impossible" to detect planets around nearby starts with an Earth bound telescope, the phrase "big bang theory" was still a derisive comment about said theory, there was still a debate about the reality of tectonic plates....the list is long and I'm only in my 50's. - This phenomena is what Asimov referred to as The relativity of wrong [tufts.edu]

Re:FSVO "about" (0)

VortexCortex (1117377) | about 5 months ago | (#45616479)

The speed of light is also by definition the fastest information can travel.

We once thought the sound barrier was unbreakable. So far no matter can travel through space faster than light, but that won't stop us from using relativity to change the definition of travel. [nasa.gov] There is a horizon beyond which we can not currently see -- Galaxies are travelling away from us faster than the speed of light from them can reach us. Aren't they traveling faster than light? Oh, that's expansion... So, if it's space that's moving then the matter doesn't have to travel through space to achieve faster than light speeds.

Of course, since you're being metaphysical, I suppose one could argue that since information is made of matter that even if FTL drives enable us to reach our destination before light would it doesn't mean that our meanings mean the same things once we do so -- The information mightn't really travel with us, it'll be different by definition when it gets there due to entropy.

Re:FSVO "about" (3, Interesting)

michelcolman (1208008) | about 5 months ago | (#45617193)

Galaxies are travelling away from us faster than the speed of light from them can reach us. Aren't they traveling faster than light? Oh, that's expansion... So, if it's space that's moving then the matter doesn't have to travel through space to achieve faster than light speeds.

That's just the result of a weird (put pragmatically practical) definition of space-time coordinates called "co-moving coordinates".

According to the "normal" rules of special relativity, the speed of light relative to us is the same everywhere, there's no such thing as "space itself expanding", and nothing goes faster than light. However, using those same definitions, we are the oldest part of the universe (using our reference system), all distant galaxies moving away from us at high speed are aging more slowly, everything gets more distance-contracted further out, and at a distance equal to the speed of light times the age of the universe, the big bang is only just beginning and time is standing still. Not just because we have to wait for the light to get here, but "right now", correcting for the travel time of light. It's just a result of relativistic time and distance contractions. Other civilisations out there will use themselves as the reference point and will have a similar view centered around them. In fact, we may say that they don't exist yet while they say we don't exist yet and both are correct from their point of view.

However, since that's not a very practical and certainly not an objective model (no matter how correct it is), cosmologists decided to use a different coordinate system. A meter anywhere in the universe is defined as what's measured by a one meter stick that is moving together with the rest of the expanding universe (undoing distance contraction), and time is defined to be the time indicated by local clocks that are also traveling together with the expanding universe (undoing time contraction). The effect is that with this coordinate system, the universe is nicely homogenous, the same age everywhere, truly infinite, and there's no longer anything special about our location.

The downside is that the speed of light is now relative to the local "expanding space", and this space can exand more quickly than the speed of light. There's nothing physical about this "space", it's just a mathematical artefact resulting from the coordinate system we chose.

Very distant objects that exist "now" in the second model, will never be visible to us because their light is trying to get to us on a kind of cosmic conveyor belt moving the other way more rapidly. In the first model, those objects don't exist yet and never will because local time has slowed down to an asymptotic halt. The definition of "now" is just "the collection of events that we happen to have assigned the same time coordinate to", and this depends entirely on the choice of coordinates. There's no such thing as an objective "now". But no matter what coordinates you use, we all agree that we will never see those objects.

Both point of view are "correct", we are just measuring things a bit differently but all conclusions are the same. And no matter what model you use, nothing can ever overtake an actual photon in vacuum. Something at a distance may move faster than a photon here, but that just depends on how we define "time", "distance" and "speed". Nothing actually goes faster than a ray of light at the same location.

Re:FSVO "about" (0)

Anonymous Coward | about 5 months ago | (#45618065)

There is a rather big difference between views of the light speed barrier now and the sound barrier in the past. By the 20th century, we were already well aware that artillery and firearms could fire supersonic projectile, and before supersonic manned flight, we had self-propelled rockets that could travel faster than sound (V2s traveled quite a bit faster). It was a question of engineering,The question was if a plane holding a person could be built strong enough and actually be controllable at such speeds (based on control problems with older planes approaching the sound barrier). That was a matter of engineering challenge. With the idea of warp drive, we still don't have any hint that it isn't barred by fundamental physical processes still. Even if you ignore the need for a yet unseen form of matter/way to manipulate space-time, there are issues like the radiation from the bubble going nuts when you exceed faster than light movement with it that may limit it to sublight speeds only (still would be really cool then). Not to mention its own share of engineering issues too, like the bubble being uncontrollable/unreachable from the inside, so you would need some slower than light control on the outside making it more like a railroad.

Re: FSVO "about" (0)

Anonymous Coward | about 5 months ago | (#45616797)

Then, if we do somehow happen upon some piece of information faster than the speed of light, we'd be able interpolate our model of the universe to another degree.

Re:FSVO "about" (-1)

Anonymous Coward | about 5 months ago | (#45615489)

is that like gay nigger butt-to-butt sex. i don't even know how it works, but i bet it smells like shame and poo.

Re:FSVO "about" (1)

timeOday (582209) | about 5 months ago | (#45616109)

It's unobservable to humans on a whole 'nother dimension anyways - duration. I don't think anything on this scale can change noticeably during our paltry lifetimes.

Re:FSVO "about" (2)

michelcolman (1208008) | about 5 months ago | (#45617223)

Well, time does slow down in the vicinity of a black hole, so they may still be "just about" to embrace, and forever will be from our point of view. Depending on what coordinate system you use, of course.

We can never actually see something cross the event horizon of a black hole, objects will always slow down to a halt before the event horizon (even though from the point of view of the object itself, time continues normally and it crosses the boundary in a finite amount of time). I expect the same is true for black holes collapsing into each other. The whole thing will just appear to freeze.

Zig-zag jet (-1)

Anonymous Coward | about 5 months ago | (#45614833)

That's when the male ejaculated prematurely.

Old news (4, Funny)

caseih (160668) | about 5 months ago | (#45614841)

Happened over two billion years ago and we're just hearing about it now!? Typical.

Re:Old news (0)

Anonymous Coward | about 5 months ago | (#45614873)

Happened over two billion years ago and we're just hearing about it now!? Typical.

You're reaching if you're looking for a laugh.

Ba dum dum...tissss...

Re:Old news (1)

thegarbz (1787294) | about 5 months ago | (#45616711)

On the upside in this case slashdot was only 0.000000000001% slower than every other news outlet. Surely this is a new speed record.

Re:Old news (0)

Anonymous Coward | about 5 months ago | (#45618095)

Thanks Obama!

Did not read article yet, but... (2, Interesting)

Anonymous Coward | about 5 months ago | (#45614855)

So.. if they observed these black holes at a few thousand light years apart, and then some time later (assuming less than a few thousand years later) at just a few light years apart... does this mean that they are moving toward each other at faster than the speed of light?

Re:Did not read article yet, but... (1)

Dunbal (464142) | about 5 months ago | (#45614937)

Either that or distance is being seriously compressed!

Re:Did not read article yet, but... (1)

ls671 (1122017) | about 5 months ago | (#45616119)

Or the black holes, due to gravitational forces affecting each other, grow in size at a rate than looks faster than the speed of light thus making them look closer.

Whatever it is, I heard that the space time continuum is affected in areas where black holes are present. It might then be hard to "see" what is really happening. The links in the summary state they aren't sure about what is going on yet.

https://en.wikipedia.org/wiki/Spacetime [wikipedia.org]

Re:Did not read article yet, but... (1)

CastrTroy (595695) | about 5 months ago | (#45615067)

I thought the exact same thing. Seems like there's some kind of contradiction. Even if they were both moving at the speed of light, toward each other it would still take many centuries for them to collide.

Re: Did not read article yet, but... (1)

todrules (882424) | about 5 months ago | (#45615513)

FTA, it was more of a generalization on 2 black holes collapsing. It wasn't talking about anything specific in this case.

Re:Did not read article yet, but... (1)

wonkey_monkey (2592601) | about 5 months ago | (#45616805)

if they observed these black holes at a few thousand light years apart, and then some time later (assuming less than a few thousand years later) at just a few light years apart...

That's a big "if." A casual reading of the summary might lead you to infer it, but it's more likely something they've extrapolated from the current observations.

Re:Did not read article yet, but... (1)

bigfinger76 (2923613) | about 5 months ago | (#45616821)

Black Hole A leaves the station at noon, travelling at the speed of light. Black Hole B leaves.... I was never good at those.

Re:Did not read article yet, but... (1)

michelcolman (1208008) | about 5 months ago | (#45617243)

They didn't actually observe the black holes spiraling towards each other. They're just looking at an image with strangely shaped jets and have come to the logical conclusion that this is what probably happened during the many thousands of years preceding the event we're witnessing now.

If they where thousands of light years apart... (1)

TheSimkin (639033) | about 5 months ago | (#45614857)

Then won't it take them thousands of years to close the gap? What am I missing here?

Re:If they where thousands of light years apart... (0)

Anonymous Coward | about 5 months ago | (#45614927)

This is where I'm confused. Seems they're saying that they're moving faster than the speed of light toward each other.. unless we've somehow been observing them much longer than we've had telescopes.

Re:If they where thousands of light years apart... (5, Informative)

Anonymous Coward | about 5 months ago | (#45614949)

They're looking at the wavy motion in the jet they put out - which is apparently showing a history of their interaction.

Re:If they where thousands of light years apart... (0)

Anonymous Coward | about 5 months ago | (#45615009)

Neat.

Re:If they where thousands of light years apart... (0)

Anonymous Coward | about 5 months ago | (#45615383)

You're missing some Austin Powers [youtube.com]

Re:If they where thousands of light years apart... (1)

wonkey_monkey (2592601) | about 5 months ago | (#45616813)

To quote todrules [slashdot.org] :

FTA, it was more of a generalization on 2 black holes collapsing. It wasn't talking about anything specific in this case.

Really? (5, Funny)

Frosty Piss (770223) | about 5 months ago | (#45614883)

Two Supermassive Black Holes About To Embrace

Kanye West and Kim Kardashian?

Re:Really? (5, Funny)

Anonymous Coward | about 5 months ago | (#45614911)

Black Holes, not assholes.

Re:Really? (1)

Uncle Mark (AUS) (2973391) | about 5 months ago | (#45615161)

Black Holes, not assholes.

Black Assholes

Re:Really? (0)

Anonymous Coward | about 5 months ago | (#45616773)

Black Holes, not assholes.

Black Assholes

I did not know that Cardassians are African American. Heck they aren't even human.

same thing in Russian (0)

Anonymous Coward | about 5 months ago | (#45615561)

http://blogs.discovermagazine.com/badastronomy/2007/06/22/black-holes-even-the-name-sucks/

Re:Really? (0)

Anonymous Coward | about 5 months ago | (#45615477)

Star Jones is about to hug Oprah Winfrey?

Re:Really? (0)

Anonymous Coward | about 5 months ago | (#45615721)

This was literally (not exaggerating) what I came to the posts to find. Kanye and Kim were the first things that popped into my head with that headline. I would also have accepted J-Lo and Pit bull . Was not disappointed.

Re:Really? (0)

Anonymous Coward | about 5 months ago | (#45616021)

Wait, you mean the original TV Batman, and some blue-faced chick that Picard banged once?

I can see the possible relevance of the latter, but are you saying Batman needs to step away from the buffet line?

Gravitational Waves (5, Interesting)

Anonymous Coward | about 5 months ago | (#45614901)

Given the countless galaxies, each with its own supermassive black hole, just like intersecting waves, the gravitational waves could theoretically act like waves in the electromagnetic spectrum, or classical physics experiments with waves. Some waves would cancel, others would be much larger than the 2 source standing waves, and thus would appear as a stronger signal to a gravitational wave detector, given said detector was sensitive enough.

Gravitational waves could also bring us closer to the point in time of the "big bang" than the cosmic microwave background radiation images. I sincerely hope this discovery, gives solid reason to develop said gravitational wave detector. Kudo's to the NASA WISE team!

Re:Gravitational Waves (0)

Anonymous Coward | about 5 months ago | (#45615877)

Now onwards to waiting the launch of the detector! Wasn't it few years from launch?

Re:Gravitational Waves (1)

Anonymous Coward | about 5 months ago | (#45617713)

You mean LISA [wikipedia.org] , a planned network of satellites monitoring the distances between them in order to detect the distortions caused by gravitational waves? That's the wrong detector for this case. Let me explain:

Gravitational waves, like all waves, have a period: the time taken for one complete wave to pass by. This period matches the characteristic period of the thing that produces them. An irregular neutron star which spins around several hundred times per second will produce gravitational waves with a period of a few milliseconds. A pair of neutron stars orbiting one another, with an orbital period of a few minutes, will produce gravitational waves with that period. And the supermassive black holes in this story, which are separated by a few light years, must take at least a few years to orbit one another, so the gravitational waves they produce will have a period of years.

Gravitational waves also have a wavelength. They travel at the speed of light, so the wavelength is equal to the distance that light travels in one period. For a period of milliseconds, that's a distance of a few hundred kilometres; for a period of minutes, it's millions of kilometres; and for a period of years, it's (obviously) a distance of light-years.

Now, here's the key bit: to detect gravitational waves, you need to use a detector with a size comparable to (within a factor of 10-100 of) the wavelength. This is why the LIGO [wikipedia.org] experiment, which uses laser beams running down tunnels a few kilometres in length, and the LISA experiment, which uses satellites flying in formation a few million kilometres apart, both exist and have separate goals: they can detect gravitational waves with periods of milliseconds or minutes respectively.

For the sort of gravitational waves produced by the system described in this story, with a period of years, there's no way we can practically build a large enough detector to detect them. But, we can cheat. Pulsars, which are ~hundreds of light-years away, produce regular signals that we can use to measure the distance to them, in the same way that LIGO or LISA measure the distance between their components. Pulsar timing array [wikipedia.org] experiments use this trick to effectively make a giant gravitational wave detector that's hundreds of light-years across.

So, in summary: the black holes described in this article should produce gravitational waves with a period of years. These waves can be detected by monitoring pulsars, turning the Earth-and-pulsars into a giant gravitational wave detector. Other types of detectors (including the planned space-based one) are designed to detect gravitational waves with shorter periods.

Re:Gravitational Waves (0)

Anonymous Coward | about 5 months ago | (#45617537)

Given the countless galaxies, each with its own supermassive black hole [...] would appear as a stronger signal to a gravitational wave detector

Unfortunately, a black hole by itself doesn't produce any gravitational waves. (It's symmetric, and you need a changing asymmetry, like two orbiting black holes, to produce gravitational waves.) But, you've otherwise got a good idea: researchers are deliberately looking for what they call a "stochastic background" from lots and lots of pairs of orbiting black holes, which should combine to produce a continuous signal from all over the sky.

Microsoft is buying Intellectual Ventures? (0)

Anonymous Coward | about 5 months ago | (#45615071)

OK, maybe I need to read TFS before posting, if not TFA...

About to (1)

reiter.john (1149557) | about 5 months ago | (#45615079)

You could say "About to" if it where 3.8 billion years ago. Just because we are about to see it doesn't change the fact that it already happened about 3.8 billion years ago.

Re:About to (0)

Anonymous Coward | about 5 months ago | (#45617947)

No, you can say about to because they're not doing it yet.

If they'd already coalesced, we would not see two black holes but one.

We see two black holes.

Not one.

Therefore they haven't coalesced yet.

Event horizons (1)

drakesword (3203755) | about 5 months ago | (#45615199)

From the blackhole standpoints they will never 'embrace'. Nor do they care, they are blackholes!

Re:Event horizons (2)

michelcolman (1208008) | about 5 months ago | (#45617269)

Actually, it's the other way around. From their point of view, they will embrace just fine. From our point of view, they never will.

If you fall into a black hole, outside observers will see you slowing down to a halt, and your watch stopping, before you reach the event horizon. For you, though, time will continue normally and you will cross the event horizon in a finite amount of time.

In fact, depending on what coordinate system you use, black holes may not even exist yet. Every "almost-black-hole" is stuck in time at the stage just before the last bit of matter falls in to make it an actual black hole. But since coordinate systems are inherently subjective, that doesn't really matter.

Obligatory Muse Reference (2)

PopeRatzo (965947) | about 5 months ago | (#45615225)

Glaciers melting in the dead of night
And the superstars sucked into the supermassive
Supermassive black hole

So what happens when two supper black hole colide? (-1)

Anonymous Coward | about 5 months ago | (#45615269)

Is this the PRON channel?

Light the candles and put on the music (0)

Anonymous Coward | about 5 months ago | (#45615369)

Once you go supermassively black, you don't go back, baby.

www.jogjacard.com (-1)

Anonymous Coward | about 5 months ago | (#45615431)

terimakasih

hmm (2)

Anonymous Coward | about 5 months ago | (#45615853)

Stupid question, but,

If they were 1000 LY's apart, and are now just "a few" LY's apart, *during the timespan of human scientific observation via modern optical tech*, does that indicate they are traveling FTL?

eg, they moved 1000 LY inside of (50?) earth years.

Re:hmm (0)

Anonymous Coward | about 5 months ago | (#45616379)

The record of their motion is embedded in the jets extending out from them, which extends back over a much longer time period than the history of astronomy.

Episode X (0)

Anonymous Coward | about 5 months ago | (#45615973)

A long time ago in a galaxy far, far away...

Two supermassive black holes are about to collide.

divide by zero (0)

Anonymous Coward | about 5 months ago | (#45616011)

So what happens when both black holes collide and suck each other in?

Re:divide by zero (2)

rsborg (111459) | about 5 months ago | (#45616557)

So what happens when both black holes collide and suck each other in?

As you read about black holes and event horizons you'll find that an external observer will never really see anything "hiting" the center of the black hole as time dilation forces the object to appear to go slower and slower as it descends the gravity well of the singularity.

In short, the heat-death of the universe will happen before we (assuming we live forever) ever find out what happens to this kind of singularity merger.

A Strange Meeting (1)

Jim Sadler (3430529) | about 5 months ago | (#45616487)

So we are to conceive the notion of two singularities merging to become one. But a singularity has zero size and therefore has zero location. And even though the two combine the size will stay the same. If i tried to make an equation with this mess it would read huge nowhere of zero size plus another huge nowhere of size equals another nowhere no larger than either of the original nowheres. So there we have it 1 plus one now equals 1. I think I need more meds.

Re:A Strange Meeting (2)

Neil Boekend (1854906) | about 5 months ago | (#45616721)

See it like this:
A black hole (size 0) combines with another black hole (size 0) to form a bigger black hole (size 0). 0+0=0 so that works.
As for location: black holes do have a location. It's at the center of their schwarschild radius.

All this is difficult to know for sure. We can hardly go and take a look.

Re:A Strange Meeting (1)

michelcolman (1208008) | about 5 months ago | (#45617279)

All this is difficult to know for sure. We can hardly go and take a look.

Sure you can! Just too bad you can't get the information back to us.

My supermassive member (-1)

Anonymous Coward | about 5 months ago | (#45617089)

You know what else is supermassive? My penis, that's what!

that's a big distance to close in on so fast (1)

BringsApples (3418089) | about 5 months ago | (#45617703)

They look out and see 2 black holes thousands of light years apart. Then they look later (not thousands of years later, mind you) and they're mere light years apart. I have such a poor understanding of how this is possible. Can anyone explain?

Re:that's a big distance to close in on so fast (1)

Urkki (668283) | about 5 months ago | (#45618059)

They're looking at the jets, which conveniently record the history of the interaction, like a recording tape that is shooting out of them.

The black holes themselves are still moving quite "normally".

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