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Virtual Telescope Zooms In On Milky Way Black Hole

samzenpus posted more than 5 years ago | from the old-bob dept.

NASA 181

FiReaNGeL writes "An international team has obtained the closest views ever of what is believed to be a super-massive black hole at the center of the Milky Way galaxy. The astronomers used radio dishes in Hawaii, Arizona and California to create a virtual telescope more than 2,800 miles across that is capable of seeing details more than 1,000 times finer than the Hubble Space Telescope. The target of the observations was the source known as Sagittarius A* ("A-star"), long thought to mark the position of a black hole whose mass is 4 million times greater than the sun. Though Sagittarius A* was discovered 30 years ago, the new observations for the first time have an angular resolution, or ability to observe small details, that is matched to the size of the event horizon."

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181 comments

obligatory (4, Funny)

savuporo (658486) | more than 5 years ago | (#24870491)

Thats your basic Beowulf cluster of telescopes.

Re:obligatory (3, Funny)

oodaloop (1229816) | more than 5 years ago | (#24870535)

In a black hole, no one can see you scream.

Re:obligatory (0, Offtopic)

laejoh (648921) | more than 5 years ago | (#24871387)

It is official; Goatse confirms: black holes are dying

One more crippling bombshell hit the already beleaguered fisting community when Goatse confirmed that fisting market share has dropped yet again, now down to less than a fraction of 1 percent of all arses. Coming on the heels of a recent Goatse survey which plainly states that fisting has lost more market share, this news serves to reinforce what we've known all along. Fisting is collapsing in complete disarray, as fittingly exemplified by failing dead last in the recent GNAA audit.

Re:obligatory (5, Interesting)

CRCulver (715279) | more than 5 years ago | (#24871385)

Thats your basic Beowulf cluster of telescopes.

Appropriate in this case, because one of the most loved science fiction tale about the galatic core is Larry Niven's Beowulf Schaeffer story "At the Core" (collected in Neutron Star [amazon.com] ). Niven, however, was writing before the idea of a supermassive black hole was current.

Nonetheless, remembering Niven's story fills me with some dread at his suggestion that the close proximity of stars at the core would set off a chain of supernovas, eventually flooding the galactic periphery with deadly radiation. Now this Slashdot post has really put a downer on my day.

Re:obligatory (3, Interesting)

nospam007 (722110) | more than 5 years ago | (#24871457)

>... Now this Slashdot post has really put a downer on my day.

Just follow the example of the Pierson Puppeteers and you'll be safe.

Black hole... where? (0)

Anonymous Coward | more than 5 years ago | (#24870495)

"Hell, I don't see anything!"

Beware (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#24870503)

A nigger bit off my penis.

Re:Beware (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#24870513)

He probably thought it was a banana. My aunt just gave birth to a niglet, good thing the toilet water was there to break the fall. Lil' buggers sure do stink.

On closer inspection (5, Funny)

nickswitzer (1352967) | more than 5 years ago | (#24870565)

An international team has obtained the closest views ever of what is believed to be a super-massive black hole at the center of the Milky Way galaxy.

*Zoom Out*... "Is that?.. It.. it.. it's Oprah eating a klondike bar. Sorry folks, our mistake."

Note (3, Informative)

Colin Smith (2679) | more than 5 years ago | (#24870569)

The milky way is our galaxy.

Also, 2 different brands of chocolate bar.

 

Re:Note (2, Funny)

aliquis (678370) | more than 5 years ago | (#24871645)

How very insightful of you, now all you need to do is to break one milky way open and look for any bubbles in it, if you find one tilt the bar so the bubbles interior don't get any light and take a photograph, send your milky way black hole to nasa.

I can do science me!

Sorry, missed a word. (1)

aliquis (678370) | more than 5 years ago | (#24871653)

milky way black hole PHOTO to nasa, eat the bar.

Pics! (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#24870579)

"Pics, or it never happened!"

Re:Pics! (-1, Flamebait)

jessica_alba (1234100) | more than 5 years ago | (#24870657)

you want a pic of total blackness? look to any republicans heart.

That's Palin. (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#24871153)

That's Palin for ya.

Re:That's Palin. (0, Flamebait)

Anonymous Coward | more than 5 years ago | (#24871755)

ah, you'd still do her. MILFy fun.

Re:Pics! (2, Informative)

Normal Dan (1053064) | more than 5 years ago | (#24870815)

Here is the actual negative surrounded by brackets:
[ ]

Re:Pics! (5, Funny)

JustOK (667959) | more than 5 years ago | (#24871337)

with the gravitational pull it would look like:

><

so.. (-1, Redundant)

Anonymous Coward | more than 5 years ago | (#24870585)

..whut? Pics or..

freeresearcher.com (4, Insightful)

Anonymous Coward | more than 5 years ago | (#24870607)

"a virtual telescope more than 2,800 miles across that is capable of seeing details more than 1,000 times finer than the Hubble Space Telescope"

- ok, but HST is an optical telescope, not "radio dish".

Re:freeresearcher.com (3, Informative)

Anonymous Coward | more than 5 years ago | (#24871449)

They both have angular resolution. The radio telescope in question still has 1000 times the angular resolution of Hubble.

What, exactly, is your peeve here?

Re:freeresearcher.com (5, Insightful)

Fred_A (10934) | more than 5 years ago | (#24871733)

"a virtual telescope more than 2,800 miles across that is capable of seeing details more than 1,000 times finer than the Hubble Space Telescope"

- ok, but HST is an optical telescope, not "radio dish".

It's all part of the same electromagnetic spectrum [wikipedia.org] . The fact that you can only see a very narrow bit of it doesn't change the fact that the rest can be used to look at things with the right tools. The only difference is wavelength. If you had the right "eyes" it would all be the same to you.

Interferometry (4, Informative)

syousef (465911) | more than 5 years ago | (#24870617)

Can we stop saying "virtual telescopes" and start using the proper grown up terms? Interferometry and Aperture Synthesis aren't hard to understand. It's a pet peeve of mine, and slashdotters should be of a level of intelligence that they can understand this stuff.

http://en.wikipedia.org/wiki/Astronomical_interferometer [wikipedia.org]

http://en.wikipedia.org/wiki/Aperture_synthesis [wikipedia.org]

Yes you get the same angular resolution as a much larger telescope (one as big as the distance between the telescopes), which is why you do it. However it's important to note that you you don't increase the amount of radiation you're collecting - it's still just the sum of the telescopes you're using.

I'll try to put it simply. Let's use optical telescopes as a familiar example. (In practice optical interferometry is much harder than radio astronomy, but I digress). The larger the diameter of the mirror (or lens) the more light we collect, and the smaller an object we can look at with reasonable detail (There is a physical relationship between the diameter of the telescope and the smallest thing you can resolve with it). We could space multiple telescopes a good distance apart and increase how small a piece of the sky we can look at in detail. The detail we could now resolve depends on the distance between the telescopes. However we're still only collecting as much light in total as the sum of the light collected by each scope. So even though we can look at a much smaller part of the sky, we won't be able to brighten up the image as much as if we had the larger telescope. It's still worth doing and it still yields discoveries, but it's not the same as having a massive telescope.

Re:Interferometry (5, Funny)

Stormwatch (703920) | more than 5 years ago | (#24870665)

Aperture Synthesis

We synthesize what we must because we can.

Re:Interferometry (1, Funny)

Anonymous Coward | more than 5 years ago | (#24871257)

Aperture synthesis

i.e., making a massive hole to let light in to see a super-massive hole which won't let light out.

No wonder you're having trouble developing the piccies!

Re:Interferometry (0)

Anonymous Coward | more than 5 years ago | (#24872089)

Aperture Synthesis

We synthesize what we must because we can.

...except for the ones who are dead.

Re:Interferometry (5, Interesting)

Maelwryth (982896) | more than 5 years ago | (#24870735)

Agreed, and in the interests of an intelligent thread (to which I should not be posting) I bring you "STRUCTURE OF SAGITTARIUS A* AT 86 GHz USING VLBI CLOSURE QUANTITIES" [iop.org] which is actually worth reading if you want to get up to date on the research into Sagittarius A*.

Re:Interferometry (4, Interesting)

Maelwryth (982896) | more than 5 years ago | (#24870817)

And this [arxiv.org] (pdf warning) might be of interest as well, as it is from S Doeleman July 2008.

STOP SHOUTING! (1)

Nursie (632944) | more than 5 years ago | (#24871531)

These days links in all caps just scream of spam.

Re:STOP SHOUTING! (3, Funny)

Anonymous Coward | more than 5 years ago | (#24871577)

Apologies, it was a straight copy and paste of the title. Luckily, I posted them in Chrome, so you may sue Google if you have suffered any permanent injuries as they hold all the rights :).

My Eyes! (1)

Nursie (632944) | more than 5 years ago | (#24871711)

Nah, no real complaint, it's just unusual to see all caps links in a legitimate comment these days.

but hey, google have money...

Re:Interferometry (3, Interesting)

jriskin (132491) | more than 5 years ago | (#24870793)

Just out of curiosity, how far could you push something like this? If you had an array of Hubble sized telescopes in space and could put them whatever distance you'd like from each other, what sort of results could you get?

Re:Interferometry (4, Interesting)

Anonymous Coward | more than 5 years ago | (#24870859)

Veery good ones, but putting a telescope in the sky is 10-100 times the cost of one on the earth. That's why they are building ALMA, and they play with VLA, and SKA (square kilometer array).

Re:Interferometry (3, Funny)

garfi5h (1130099) | more than 5 years ago | (#24871533)

... and they play with VLA, and SKA (square kilometer array).

Cool! Can they play reggae or jazz to? ;-)

"Darwin" (5, Interesting)

Herve5 (879674) | more than 5 years ago | (#24871709)

Indeed the European Space Agency has had such a project for years: a space optical interferometer named Darwin, with an additional twist: by using descructive interferometry instead of constructive one, they intend to switch off a star in the center of the field of view, to see the planets around (these ones being way darker you wouldn't detect them otherwise), analyse the molecules in them etc. Needless to say, this project is still in its early phases, but indeed appears, with a schedule, in ESA's plans. http://en.wikipedia.org/wiki/Darwin_(ESA) [wikipedia.org]

Space Interferometry Mission (SIM) (5, Informative)

mbone (558574) | more than 5 years ago | (#24871957)

If you had an array of Hubble sized telescopes in space and could put them whatever distance you'd like from each other, what sort of results could you get?

That is basically the Space Interferometry Mission (SIM) [nasa.gov] , which alas has had funding troubles recently. The component telescopes are not the size of the Hubble, but the idea is exactly as you suggest. One thing you could do with this is detect Earth sized planets in a solar system like ours out to a reasonable distance.

Re:Interferometry (2, Funny)

SJ2000 (1128057) | more than 5 years ago | (#24870935)

Can we stop saying "virtual telescopes" and start using the proper grown up terms? Interferometry and Aperture Synthesis aren't hard to understand. It's a pet peeve of mine, and slashdotters should be of a level of intelligence that they can understand this stuff.

So in layman's terms, speedy thing goes in, speedy thing comes out?

Re:Interferometry (4, Informative)

Shag (3737) | more than 5 years ago | (#24870957)

Yes. Please.

And while we're at it, can article-writers stop referring to the submillimeter/microwave portion of the spectrum as "radio"?

Linking together radio dishes is not a big deal - radio astronomy goes back to the 1930s, and the Very Long Baseline Array has stretched from Hawaii to the Virgin Islands for decades now.

Linking together JCMT and SMA with some dishes on the mainland is a big deal in submillimeter astronomy. The Cosmic Microwave Background wasn't even discovered until the 1960s, and then it took another couple decades to develop serious observing capabilities. There's plenty of interferometry on Mauna Kea, both within the SMA and between the SMA and JCMT and/or CalTech Submillimeter Observatory, but that's all relatively short-baseline.

Re:Interferometry (3, Informative)

caluml (551744) | more than 5 years ago | (#24871283)

And while we're at it, can article-writers stop referring to the submillimeter/microwave portion of the spectrum as "radio"?

Just out of interest, why? It is part of the RF spectrum, just way way way up there. It's also good to call it that, because it reminds people that it's part of the same thing as light, xrays, Ham Radio, and mobile phones.

Re:Interferometry (2, Insightful)

dreamchaser (49529) | more than 5 years ago | (#24871073)

The thing that plugs into your cable or DSL isn't really a 'modem' either but that doesn't stop people from calling it one. 'Virtual telescope' is far easier for laymen to grasp. Yes, slashdotters can for the most part understand this stuff, but your pedantry isn't really called for.

Re:Interferometry (-1, Flamebait)

syousef (465911) | more than 5 years ago | (#24871611)

First of all "Modem" is a layman's term? Gimme a break? You analogy is weak as piss.

Secondly Pendantry???? I explained how things worked in simple terms. When you talk about "Virtual Telescopes" to describe interferometry it's like talking about a virtual go pedal instead of an accelerator in a car. Or perhaps a better analogy isn't modem for a DSL device but "brain" when talking about a CPU. The atricle was a science article for "nerds". It shouldn't resort to baby talk.

You're just an attention seeking troll.

Re:Interferometry (2, Insightful)

Anonymous Coward | more than 5 years ago | (#24872015)

He might be an attention seeking troll but he's right. If somebody says virtual telescope, I can sort of relate to what they're talking about. If they use "Interferometry and Aperture Synthesis", I'll just go "Some boring shit" and go away. You might have not enough of a life to actually use these terms, but the average slashdotter doesn't even know what they mean.

Re:Interferometry (0, Flamebait)

Curtman (556920) | more than 5 years ago | (#24871639)

Interferometry and Aperture Synthesis aren't hard to understand. It's a pet peeve of mine, and slashdotters should be of a level of intelligence that they can understand this stuff.

Really. Whiny bitches are a pet peeve of mine.

Re:Interferometry (2, Interesting)

john83 (923470) | more than 5 years ago | (#24871719)

A related concept, which I find interesting, is that the diameter of telescopes on earth isn't really the limiting factor. In the ideal situation, yes, a bigger aperture gives you better resolution, but in practice, you have to compensate for atmospheric turbulence first, using something like adaptive optics (where you use a deformable mirror). I've been told that some telescopes (like the Pan Starr) now do this step digitally.

Re:Interferometry (1)

Snaller (147050) | more than 5 years ago | (#24871739)

"lashdotters should be of a level of intelligence that they can understand this stuff."

Since when?

Re:Interferometry (4, Insightful)

eclectic4 (665330) | more than 5 years ago | (#24871761)

"Interferometry and Aperture Synthesis aren't hard to understand."

Then...

"I'll try to put it simply..."

And with two wiki links included? Sheesh... now I know you stated that /.ers "should be of a level of intelligence that they can understand this stuff", which I believe is true enough, but you greatly underestimate our laziness. "Virtual telescope" works just fine for me... IANAA, and I never will be, sorry.

Re:Interferometry (1)

syousef (465911) | more than 5 years ago | (#24871803)

And with two wiki links included? Sheesh... now I know you stated that /.ers "should be of a level of intelligence that they can understand this stuff", which I believe is true enough, but you greatly underestimate our laziness. "Virtual telescope" works just fine for me... IANAA, and I never will be, sorry.

Well then why bother to read the article at all?

Better yet, if you're so lazy why reply like this? You could have spent the same amount of time skimming one of the articles.

Re:Interferometry (2, Informative)

mbone (558574) | more than 5 years ago | (#24872025)

Yes, but in astronomy virtual telescope generally means a computer compilation of various sky surveys [nasa.gov] , so you can type in a coordinate and see what is there. This is totally different, VLBI provides a real telescopic view, just synthesized by interferometry.

As an analogy, Google Earth is a virtual spy satellite. An orbiting synthetic aperture radar is a real spy satellite, just with a synthesized image.

Re:Interferometry (1)

hesaigo999ca (786966) | more than 5 years ago | (#24872059)

What if, we had a telescope that was 30,000 feet long, meaning it was going upwards towards the sky, as in a sky elevator incorporating a telescope into itself .... I am not sure but the width of this elevator, which I don't know whether they are still working on, would be wide enough to fit a telescope into no??? this would yield the longest telescope and allow for us to see Oprah eating her klondike bar INSIDE the black hole...

Obligatory (4, Funny)

bemo56 (1251034) | more than 5 years ago | (#24870645)

Black Holes suck!

- I'll be here the whole week. Tip your waitress. Try the veal.

Pics? (5, Funny)

Feanturi (99866) | more than 5 years ago | (#24870655)

Pics or it didn't happen

Re:Pics? (4, Funny)

Psychotria (953670) | more than 5 years ago | (#24870739)

Pics or it didn't happen

I believe that the pictures look pretty similar to the screenshots of Doom 4.

Re:Pics? (0)

Anonymous Coward | more than 5 years ago | (#24871643)

I was thinking of screenshots of Duke Nukem Forever but as I remember, those have been around for years, also waiting for DNF.

Re:Pics? (0, Redundant)

Gewalt (1200451) | more than 5 years ago | (#24871681)

*whoosh* gp was referring to the notion that it was too dark to see anything. nothing but black.

Re:Pics? (2, Funny)

dvh.tosomja (1235032) | more than 5 years ago | (#24870813)

PICS OR GTFO

Help Wanted? (2, Insightful)

Nymz (905908) | more than 5 years ago | (#24870983)

Pics or it didn't happen

Oh, we have lots of pretty pictures (of colorful surrounding gas). We just don't have enough picture details to determine what it is, that is happening.

What we could really use, like out of a science fiction story, is to stumble upon an ancient astronomer's time-lapse photo project. About 10-20 million years should be sufficient. But in case our stumbling plan fails, how would like to go down in history, sayyyy in 10-20 million years from now, as the guy who got the ball rolling?

Re:Pics? (5, Funny)

suds (6610) | more than 5 years ago | (#24871017)

Here is one high resolution picture of the blackhole

.

Re:Pics? (1)

tom_75 (1013457) | more than 5 years ago | (#24871985)

Damn, I thought I had a dead pixel. But then I scrolled down. Barely though... Must have been your black hole pulling back on my page :)

Re:Pics? (1)

RedWizzard (192002) | more than 5 years ago | (#24871477)

Pics or it didn't happen

Here you go. [photobucket.com]

First pics released! (5, Funny)

TechnoBunny (991156) | more than 5 years ago | (#24870753)

HeRE! [photobucket.com]

Re:First pics released! (1)

Fex303 (557896) | more than 5 years ago | (#24870847)

Modded down as troll and a link going to Photobucket. How could I resist the temptation to click on a link like that?

I was expecting something eye-scarringly horrific, instead I came out vaguely disappointed, yet also somewhat relieved.

Well played, sir.

Re:First pics released! (1)

Missing_dc (1074809) | more than 5 years ago | (#24871251)

I was expecting something eye-scarringly horrific, instead I came out vaguely disappointed, yet also somewhat relieved.

I hear there is even a video:

http://www.youtube.com/watch?v=oHg5SJYRHA0 [youtube.com]

(Sorry, couldn't resist)

so... (2, Funny)

Brain Damaged Bogan (1006835) | more than 5 years ago | (#24870755)

the moon and various satellites spin around the earth
the earth and various other planetary objects spins around our sun
our sun spins around a giant black hole
what does the giant black hole spin around?

Re:so... (2, Funny)

Psychotria (953670) | more than 5 years ago | (#24870807)

Well, duh [megomuseum.com]

Re:so... (5, Funny)

Anonymous Coward | more than 5 years ago | (#24870831)

> what does the giant black hole spin around?

Windows Vista

Re:so... (1)

catmistake (814204) | more than 5 years ago | (#24871159)

One might postulate that our galaxy & its satellites may revolve around the center of gravity of the Local Group of galaxies... but I think that's thought wrong now... apparently all the galaxies are rapidly moving away from each other faster and faster in all directions, as though the universe were flying apart; it seems its expanding from all points (think of raisens in rising dough, or dots drawn on a balloon as its inflated).

Re:so... (2, Insightful)

MosesJones (55544) | more than 5 years ago | (#24871541)

The only thing in the Universe that is more dense and unexplained

The intelligence and Ego of George W Bush

Re:so... (5, Funny)

bobdotorg (598873) | more than 5 years ago | (#24871655)

the moon and various satellites spin around the earth
the earth and various other planetary objects spins around our sun
our sun spins around a giant black hole
what does the giant black hole spin around?

An exceptionally massive turtle.

One wonders (1)

duanemc (758821) | more than 5 years ago | (#24870777)

exactly how much "fine detail" it is possible to make out in an object from which light does not escape...

event horizon? (1)

someone1234 (830754) | more than 5 years ago | (#24870987)

Where you read that there is no light to escape from the event horizon?
As far as i know, it is the source of extreme radiation.

Re:event horizon? (2, Informative)

mbone (558574) | more than 5 years ago | (#24871905)

There is an accretion disk around the event horizon, where things (dust, gas) are orbiting around at nearly the speed of light. As these things rub together, and as new stuff gets added, there is lots of energy to be detected far away - especially in jets of very hot matter out of the poles.

The event horizon itself, for a black hole of this size, is not detectable. (Very small black holes should glow with Hawking radiation.)

Re:event horizon? (2, Informative)

NormalVisual (565491) | more than 5 years ago | (#24871975)

By definition, the event horizon is the area surrounding a black hole inside which the escape velocity exceeds the speed of light, therefore you can't see anything beyond it. You're probably thinking of the accretion disk.

Re:One wonders (1)

Maelwryth (982896) | more than 5 years ago | (#24871021)

They aren't dealing in light. From the article;

The astronomers linked together radio dishes in Hawaii, Arizona and California to create a virtual telescope more than 2,800 miles across that is capable of seeing details more than 1,000 times finer than the Hubble Space Telescope.

It is rather a bad analogy isn't it.

Re:One wonders (1)

statemachine (840641) | more than 5 years ago | (#24871059)

They aren't dealing in light. From the article

Well of course they aren't! From the submission:

super-massive black hole

Re:One wonders (1)

Maelwryth (982896) | more than 5 years ago | (#24871323)

I assumed he/she/it had been confused by the Hubble reference since one of the methods of detecting a black hole is through the gravitational lensing of light.

OT - your sig (1)

neumayr (819083) | more than 5 years ago | (#24872043)

Why can't I https://slashdot.org/ [slashdot.org] ?

What would be the point?
It'd just be a massive waste of resources. https is pretty expensive, especially given the amount of traffic this site gets.
If you're worried about sending your unencrypted password through the tubes, I don't know, use tor or something, at least makes it less likely for someone who's after you personally to get your login data.

Re:One wonders (1)

NormalVisual (565491) | more than 5 years ago | (#24872017)

Radio and light are all part of the same electromagnetic spectrum, so the parent poster's question is still legitimate as no radiation will be able to escape the black hole proper. To answer though, scientists obviously won't be able to see past the event horizon, but they may be able to image the finer details of the area immediately surrounding it which are also of intense interest.

also... (1)

Brain Damaged Bogan (1006835) | more than 5 years ago | (#24870797)

If the universe is expanding does that mean that the gravity at the center of the blackholes in each galaxy is getting weaker as time passes?, I thought that as black holes sucked in more matter the gravity would get stronger.

Re:also... (5, Informative)

Muczachan (1012169) | more than 5 years ago | (#24870867)

Nope. Gravitic force gets weaker the further you get from the mass exerting it.

Re:also... (1)

Psychotria (953670) | more than 5 years ago | (#24870883)

It might be related, I dunno (I am not a physicist, nor very good at maths), but as the black hole captures more mass it (intuitively) becomes more massive. As the mass increases shouldn't the "attraction" (i.e. gravity) between the black hole and matter external to the event horizon also increase. The point I am trying to make is that if the mass of the black hole can be infinite (it keeps collecting mass...), wouldn't that also mean that as the mass of the black hole approaches infinity that the speed of stuff being accelerated towards it also increases. And, if the mass of the black hole is approaching infinity, can the speed of the stuff being dragged in approach the speed of light?

Re:also... (0)

Anonymous Coward | more than 5 years ago | (#24870971)

I might be wrong on this...yes the stuff being dragged in can approach the speed of light (I can to by running) but can never get there. It would change state before then (I am unsure whether state is the right word for that). Also if it did approach the speed to light, then it's mass would approach infinity as well. From my experience (none) scientists hate infinities because you can't get any information from your data without getting rid of them.

expanding ... (4, Insightful)

rohan972 (880586) | more than 5 years ago | (#24871401)

http://dictionary.reference.com/search?q=expanding [reference.com]

To determine that something is expanding you must first know its dimensions. Since we don't know the dimensions of the universe, we can't really tell if it is expanding or not. There is movement within the observed portion of the universe that is compatible with the concept of an expanding universe.

Black hole gravity (2, Interesting)

mbone (558574) | more than 5 years ago | (#24871881)

General relativity makes no predictions about what is happening at the center of black holes - there is a singularity in the equations there. Worse, in general relativity singularities are (probably) never "naked" - if you go in to see what is happening you can never come back out, or send a signal back out, to tell us about it.

But, yet, the gravity of the black hole, as experienced outside, does increase with time as things get sucked in.

Re:also... (2, Interesting)

AP31R0N (723649) | more than 5 years ago | (#24871933)

Also, the expansion takes the form of things moving away from each other, not themselves getting bigger. Black holes don't suck things in anymore than the Earth sucks in the moon. If you get close enough, yeah, you'll fall in. But it's not like water going down a drain, or a vacuum. There are black holes in the center of the galaxy that are frighteningly huge, millions of solar masses... that aren't gobbling up stars. While their gravity is strong, the distances involved quickly makes the pull very weak. That and there are other objects pulling in every other direction.

Interesting side bit - Small black holes evaporate over time. Virtual particles pop outside the event horizon and sometimes escape, becoming real. Over enough time the black hole fizzles away. How that works exactly you'd have to ask Hawking.

Any physicists on hand to clarify/correct? /long fascinated by black holes

Re:also... (2, Insightful)

TheRaven64 (641858) | more than 5 years ago | (#24872005)

No. You have distance, rate of change of distance (speed) and rate of change of speed (acceleration). Gravity provides an acceleration, which is dependent on distance (meaning that you have a rate of change of acceleration due to gravity, which is what makes orbital calculations tricky). If two objects are moving away from each other, they have an initial speed. Gravity will be applying a force on them, which will be decreasing their speed, but their distance will keep increasing. As the distance increases, the effect of gravity decreases (it's proportional to the inverse of the square of the distance). As such, objects can continue to move away from each other (i.e. the volume encompassed by the distance between them will expand) without any reduction in gravity. The question is whether the initial impulse was enough to allow them to keep moving away from each other (continual expansion theory) or whether they will eventually start moving back towards each other and then collapse (big crunch theory).

Re:also... (2, Interesting)

tinkerton (199273) | more than 5 years ago | (#24872135)

If you'd replace the sun with a black hole of the same mass, the earth would remain on the same orbit as it does now. A black hole doesn't pull any harder than another object of the same mass.

It's only when you get close that things start to change. Gravity is zero if you're 3km from the center of the sun, but with its black hole replacement, it would be impossible even for light to get away from it.

Black hole (0)

eclectro (227083) | more than 5 years ago | (#24870863)

It's the reason slashdot has URL data in posts.

Paths (5, Funny)

Anonymous Coward | more than 5 years ago | (#24870889)

Sagittarius A* ?
Dijkstra's Scorpio is better :)

Ok ok, I'm not a space nerd!

Muse (5, Funny)

invisiblerhino (1224028) | more than 5 years ago | (#24870967)

As a physicist, I sometimes wish I could hear the words 'supermassive black hole' in a professional context without immediately thinking of that catchy song from their new album.

thank heavens! (0)

paniq (833972) | more than 5 years ago | (#24871077)

At a first quick glance, I thought the title referred to the subject of a spam mail advertising for a pornsite.

Reading the article, I am sad now that it doesn't.

Idle musing- any artificial structures/phenomenon? (0)

Anonymous Coward | more than 5 years ago | (#24871305)

So anyway, here's hoping they see something REALLY unusual. Like some point sources of radiation in a perfect geometric pattern. Or a "real" pulsar (not an annoying neutron star) that emits a signal like clockwork.

I mean, they're looking at the center of the galaxy so hopefully a super advanced civilization could put up a big beacon there (GPS for the galaxy). Or maybe just some art. Many Sci-Fi writers have posited that the center of the galaxy would be where all the super aliens would go. (Of course it could also be the worst place, like in Vernor Vinge's novels).

I mean, we're spending billions looking for microbes in Martian dust and (will be) analyzing a few faint photons from the reflections of exo-planets looking for oxygen. I hope we don't ignore a type III civilization broadcasting its presence in the most logical place we could look.

Heck I'd believe in God if I saw a giant cross there!

stupified by ads (-1, Offtopic)

Anonymous Coward | more than 5 years ago | (#24871307)

not on the subject, but I felt totaly stupified by the 'flat stomach', fitness add on a ./ page. I am a newcommer and not competent in the ./ culture but think that ads should be in harmony with the site's orientation

Re:stupified by ads (1)

daveime (1253762) | more than 5 years ago | (#24871701)

Like um ...

Cheetos, Kool-Aid, Hot Pockets, Zena Tapes, Inflatable Dolls, Basements for Rent etc ?

The Biggest....? (3, Funny)

Frightened_Turtle (592418) | more than 5 years ago | (#24871785)

Hmm..... Near the "A-Star"?

Does this mean that in the center of our galaxy is the biggest "A-Hole" in our galaxy?

So... (1)

ImYY4U (539546) | more than 5 years ago | (#24871789)

How exactly do we get "pictures" of a black hole, if light can't escape? Isn't a picture of a black hole basically just a picture showing nearby light and stars etc. spinning around the event horizon?

Virtual Telescope ? (1)

mbone (558574) | more than 5 years ago | (#24871857)

Gee, after 40 frigging years of VLBI you think people would have some clue about aperture synthesis. It ain't no virtual telescope, it's just as real as any other, it's just that the images are done after the fact.

From TFA (1)

tom_75 (1013457) | more than 5 years ago | (#24871935)

"The new observations have a resolution equivalent to being able to see, from Earth, a baseball on the surface of the moon." Screw baseballs, I want to see the American flag waving on the Moon.
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