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Astronomers Planning To Image Milky Way's Central Black Hole
99luftballon writes "Astronomers are planning the Event Horizon Telescope project in Arizona on Wednesday — and say in three or four years they should be able to image the ring of matter around the supermassive black hole at the center of the Milky Way. The black hole is 26,000 light years away, but should be large enough to check if Einstein got his equations right."
Will people ever stop checking your equations?
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but should be large enough to check if Einstein got his equations right.
The ongoing thingy with CERN's maybe-FTL neutrinos may answer that before the three or four years envisioned for this.
Sheesh, evil *and* a jerk. -- Jade
I don't see why they're building such a telescope, because where we're going, we won't need eyes to see.
It's black. Duh.
All these posts in a story about a "black hole" and not one goatse link?
They're not imaging the event horizon, they're trying to image the accretion disk around the central black hole, and hoping they can see the event horizon's "shadow" against it. I doubt that we're going to be directly imaging the event horizon for the central black hole anytime soon.
The Milky Way's central black hole is 4.l million solar masses. The Schwartzchild radius of a static black hole of that mass is roughly 12.3 million km, or 17.7 x the radius of our sun. That's roughly 1/3 the size of Mercury's orbit. You could put it in the center of our solar system, and not devour a single planet (though they would start orbiting a *lot* faster).
Hold out your fist at arm's length. If you put the Milky Way's central black hole where our sun was, it would be roughly that big.
Now, imagine trying to see something that size, which is perfectly dark, from 27,000 light years away and you'll understand how difficult it would be to directly image it.
They've got a picture of it up on Wikipedia, but not for much longer!
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
It might be a bit of an oversimplification to call this a test of relativity.
Relativity consists of special relativity (SR) and general relativity (GR). GR includes gravity.
SR has been tested in many different ways to extremely high precision. Here is a summary of experimental tests of SR. Note that even if the faster-than-light neutrino result from CERN/Gran Sasso is correct, it doesn't necessarily conflict with SR. SR doesn't forbid FTL. It only forbids an object from being accelerated from a speed less than c to a speed greater than c.
Here is an article on tests of general relativity. A nice popularization of this kind of thing is the book Was Einstein Right? by Clifford Will. Although GR has not been as thoroughly tested as SR, it has been tested in many different ways. There is not really a heck of a lot of doubt that it's right in many ways. Alternative theories exist, but they are extremely tightly constrained by observation.
We expect that Sagittarius A* is a black hole, and the definition of black hole basically means that it has an event horizon. If, contrary to everyone's expectations, it turns out not to have an event horizon, the most likely interpretation may not actually be that GR is wrong. It may actually mean that there is something wrong with relativistic particle physics. It's possible that the process of formation that we think leads to a black hole actually stops short of forming a black hole, and instead forms some other exotic object. There are various speculations about these things: gravastars, fuzzballs, quark stars, boson stars, q-balls... If we found out that Sgr A* was one of these hypothetical critters, it would be very exciting for the particle physicists, but it would not disprove GR.
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I think it's a reference to the movie Event Horizon
(Pretty creepy movie, BTW)
It turns out there is no black hole at the centre of the Milky Way?
Michael
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The telescope that they use is actually several radio telescopes capturing the same signal at the same time, in an observing mode called VLBI for Very Long Baaseline Interferometry. The data captured are correlated off-site (or in real time if they can build a trans-oceanic Gbyte/sec data link) to get a wave-by-wave signal match, producing interference fringes that permit the construction of a very high resolution image. These days, they store the GByte/sec data on a bank of hard disk drives and FedEx them to the correlator in Virginia.
I happen to work on one of these telescopes, the Heinrich Hertz Submillimeter Telescope on Mt. Graham in Arizona. We have a hydrogen maser on site to produce a clock accurate enough to collect the data synchronously with other telescopes in other parts of the world.
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Holy crap! It's the lesser known cubic blockhole ... much more sneaky and secretive than blackholes.
I spell goodly! :-P
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This "shill" crap that has been flying around lately has to stop. It's restricting a variety of viewpoints from participating on the site and creating an echo chamber.
No it doesn't. You can post anything you want here (except Scientology secrets).
And if you expect moderation to serve as an "invisible hand" that optimizes post ratings, you must be new around here.
But you're welcome to tell us why you're so sensitive about this that you have to spam your complaint on every story. You wouldn't happen to be an astroturfer yourself, would you?
Sheesh, evil *and* a jerk. -- Jade
Maybe they should check Uranus if they are looking for central black holes. I hear it might be supermassive.