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Black Hole Gobbles Up A Star
May 2, 2012 7:52 PM   Subscribe

Two Billion years ago a black hole swallowed a star.
posted by holdkris99 (34 comments total) 8 users marked this as a favorite

 
I enjoy that introductory sentence. For some reason, I want it to be the first thing I say to everyone I see tomorrow.

"Hey, are you free to have a 10 am meeting on the newest filings this morning?"
"Two billion years ago, a black hole swallowed a star."
". . . What?"
"Yes, 10 am is fine. Thanks!"

"Paper or plastic?"
"Two billion years ago, a black hole swallowed a star."
"I'm sorry -- paper?"
"Yes, paper. Thanks."
posted by Countess Elena at 8:13 PM on May 2, 2012 [17 favorites]


Now imagine rob halford screaming that in a ear-piercing falsetto
posted by falameufilho at 8:29 PM on May 2, 2012 [10 favorites]


Now I'm hungry for some reason.
posted by hot_monster at 8:40 PM on May 2, 2012


Scientists first caught a black hole red-handed in a stellar murder last year.


Oh the stupid! It hurts me so..
posted by c13 at 8:48 PM on May 2, 2012


Metafilter: an unlucky star whose death may ultimately provide more clues on the inner workings of the enigmatic gravitational monster that devoured it.
posted by michaelh at 9:36 PM on May 2, 2012


Take one down, pass it around, One Billion Nine Hundred Ninety-Nine Million Nine Hundred Ninety-Nine Thousand Nine Hundred Ninety Nine years ago a black hole swallowed a star.
posted by Metro Gnome at 9:50 PM on May 2, 2012 [11 favorites]


that's pretty

the pop-up ad offered a pizza cutter shaped like the star trek enterprise
posted by pyramid termite at 2:28 AM on May 3, 2012 [3 favorites]


"2.7 billion light-years away.

Holy god that is some mind-blowing distance. To think that a 6ft human can see that far is astounding. On a lighter note, Suvi Gezari would make a great band name.
posted by marienbad at 3:28 AM on May 3, 2012


"Hey, are you free to have a 10 am meeting on the newest filings this morning?"
"Two billion years ago, a black hole swallowed a star."
". . . What?"
"Yes, 10 am is fine. Thanks!"


After reading this, I now have some sort of weirdly awesome Office Space/Firefly mashup playing in my head.
posted by RonButNotStupid at 3:36 AM on May 3, 2012 [2 favorites]


That star isn't dead. It's just now five billion years in the past trying to get its parents to kiss.
posted by localroger at 5:04 AM on May 3, 2012 [4 favorites]


Rob Halford? Seems like more of a Chris Cornell lyric
posted by Renoroc at 5:05 AM on May 3, 2012 [2 favorites]



Holy god that is some mind-blowing distance. To think that a 6ft human can see that far is astounding. On



You probably think we actually landed on the moon, too. WAKE UP SHEEPLE
posted by spicynuts at 5:06 AM on May 3, 2012 [3 favorites]


Holy god that is some mind-blowing distance. To think that a 6ft human can see that far is astounding.
You say astounding, but believe me it's just plain depressing and infuriating when you're trying to catch photons that've travelled that far (or much much further) and they get stopped in the last couple of hundred feet by a cloud.
posted by edd at 5:07 AM on May 3, 2012 [3 favorites]


I work on the telescope that was used to discover this!
posted by capnsue at 5:30 AM on May 3, 2012 [4 favorites]


Let me clarify -- I work on PanSTARRS but not the actual telescope part -- I work on the gigantic science database side of it (PSPS or PanSTARRS Published Science.) Everyone here is pretty psyched about this.
posted by capnsue at 5:38 AM on May 3, 2012


[Black holes] can rip apart passers-by, gravitationally pulling at stars in gigantic versions of how our moon tugs on Earth's oceans to generate tides.

Oy. Gotta love science journalism written at a third-grade level.

Awful writing aside, this is pretty cool
posted by trunk muffins at 5:46 AM on May 3, 2012 [2 favorites]


When the star is ripped apart by the gravitational forces of the black hole, some part of the star's remains falls into the black hole while the rest is ejected at high speeds

Can someone explain to me how if the black hole 'rips' shit apart by gravitational pull it can spit out the star at the same time? I mean, it's either a completely inescapable gravitational object or it isn't, right? Or is the ejection occurring at the other end of the hole?
posted by spicynuts at 6:36 AM on May 3, 2012


spicynuts, to begin with, the part we can see is not inside the "event horizon", beyond which the black hole becomes a completely inescapable gravitational object. In analogy to a waterfall, what we can see hasn't gone over the edge yet, and might yet make it away safely.

A lot of interesting things happen at and near the event horizon - massive time dilation for one, and Hawking radiation. I'll defer explaining what Hawking radiation is, but suffice it to say: if you tear apart a star, there's going to be explosive side effects. (Again, in analogy, a Pro Tip: Don't stand right beside a car-crushing machine. Chunks of non-crushed car may enter - and exit - your body!)
posted by IAmBroom at 7:22 AM on May 3, 2012


Oh, one thing I forgot to say: we are not seeing most of the star; likely just a tiny portion. The time duration here is measured in days; the outer layers are being superheated, and glowing massively brighter than the original star ever did. "The candle that burns brightest..."
posted by IAmBroom at 7:24 AM on May 3, 2012


Can someone explain to me how if the black hole 'rips' shit apart by gravitational pull it can spit out the star at the same time?

IANAScientist, and I think shitty science journalism is partly at fault here, but my guess is that only part of the star is getting sucked into the black hole. As it gets ripped apart, some goes in to the black hole, but some remains above the event horizon. That part that remains above the event horizon gets slingshotted around the black hole by the tremendous gravitational pull, and then 'ejected' back out into space (though 'ejected' really is the wrong word, since it never went into the black hole).

But -- just my guess from watching the vid.
posted by Capt. Renault at 7:45 AM on May 3, 2012 [1 favorite]


Can someone explain to me how if the black hole 'rips' shit apart by gravitational pull it can spit out the star at the same time? I mean, it's either a completely inescapable gravitational object or it isn't, right? Or is the ejection occurring at the other end of the hole?

Capt. Renault has it pretty spot on - the star covers some region of space and since gravity gets stronger the closer you are, the part of the star closest to the black hole gets pulled on harder than the outside part. If the difference in gravitational pull is bigger than the gravity of the star holding itself together it gets "tidally disrupted" and part of it gets torn off into the accretion disk of the black hole and eventuall falls in.
posted by Zalzidrax at 10:50 AM on May 3, 2012


The term I've heard for the effect of the tidal forces is "spaghettification", because the stronger gravitational attraction at one end pulls everything into a long thin shape.
posted by benito.strauss at 12:42 PM on May 3, 2012


For energy generation by a black hole it's - well, messy. There's massive heat generation in the accretion disk, probably strong magnetic fields and other stuff going on. The best guess as I understand it as to how the energy gets spat out so dramatically is the Blandford-Znajek mechanism.

Hawking radiation is completely irrelevant here - it's absolutely bogglingly tiny for a black hole the mass of the Sun and gets weaker the bigger the black hole is. For a supermassive black hole it's completely drowned out. It's [finds back of envelope] about 5x1013 times colder than the cosmic background - a black hole like that grows way faster by sitting their sucking up microwaves than it grows smaller by Hawking radiation (but still at a tiny rate due to it).
posted by edd at 1:33 PM on May 3, 2012 [1 favorite]


Doesn't anyone else find this sexy? Aww yeah baby, I got way past her event horizon, and there's no going back!
posted by Halloween Jack at 2:49 PM on May 3, 2012


Anyone have any idea how long this would've taken? I can see from the pic that everything's good in 2009 and then in 2010 it goes kablooie, but did it take a month? a day? I'm guessing the last little bit of the star's life would be pretty short because Huge Black Hole!, but I wonder how short.
Also capnsue has a pretty sweet gig going there! Yay!
posted by Zack_Replica at 3:38 PM on May 3, 2012


If you were in orbit around the Earth with your feet pointed toward the center of the Earth, your feet would want to orbit slightly faster than your head. But since your body doesn't want your feet drifting away from your head, you would feel this as a slight force trying to tug them apart, hopefully unsuccessfully. The taller you are the stronger this effect would be, and the closer you are to the mass you're orbiting the stronger it is.

Stars are big, and black holes are very small for their gravitational fields, and so stars can reach the point where this tugging force is strong enough to overcome the gravitational attraction that normally holds them together. Before the star comes completely apart, since it's made of gas, material is drawn off of the nearest and furthest points. The near side material generally enters the accretion disk, because its problem is that it's not orbiting fast enough to overcome the hole's gravity. On the star's far side material is drawn off because it's orbiting too fast and wants to fly outward harder than the hole is trying to pull it in.

When the star finally comes apart this is a very dramatic event because there is a lot of energy in a star and what keeps the star from blowing up on a normal day is gravity. Eventually the star's inner energies start pushing material out the inner and outer weak spots faster than gravity is pulling, and the large masses of gas ejected this way on the outer or trailing tidal tap often manage to climb back out of the hole's gravity well. (In fact they're sometimes going a substantial fraction of the speed of light.)

The energy to do this comes from the rest of the star's matter giving up potential energy as it is drawn into the hole, and the star's own internal energies which are released like a shaped charge nova.

Things are complicated if the star is spinning and by magnetic fields, which can take energy from stuff flying here and add it to stuff flying there and focus the ejecta stream.

The final disintegration, from the star still resembling a star if a bit stretched through what might be several explosions and finally no single object much resembling the original star, takes a few hours to a few days depending on the star and the black hole.
posted by localroger at 3:50 PM on May 3, 2012 [3 favorites]


Ok so the black hole doesn't "eject" anything... The star is being torn apart and disintegrates in all directions. I can't say I have any sympathy... Stars are assholes
posted by spicynuts at 5:45 PM on May 3, 2012 [2 favorites]


everybody is a star ....
posted by pyramid termite at 6:48 PM on May 3, 2012


Stars are assholes

Sol is holding on line 1. It wants to know if you'd like this summer thing to continue.
posted by localroger at 7:23 PM on May 3, 2012


spicynuts: Generally black holes do eject - material is often preferentially spat out along the black hole's axis of rotation in extremely fast jets.
posted by edd at 2:18 AM on May 4, 2012


While it's said that "black holes eject matter," technically what's happening is that the swirling mass of crap surrounding the black hole is ejecting, with the ejections powered by the compression and acceleration of other stuff that ends up going down the hole. Once something is past the event horizon it's going nowhere.

Of course there is a little paradox here because there is a time dilation effect that reaches infinity at the event horizon, meaning that nothing ever actually crosses the event horizon of a black hole in finite time for the outside world. Which kind of makes it interesting to ask how the black hole forms in the first place...
posted by localroger at 5:48 AM on May 4, 2012 [1 favorite]


It looks like that from the outside, but things falling in do so in finite proper time from their own point of view (see here for example for a bit more explanation).
posted by edd at 5:52 AM on May 4, 2012 [1 favorite]


That's a good link edd. I think it blows a major hole in the plot of Pohl's Gateway series, though.
posted by localroger at 6:50 AM on May 4, 2012


Yeah I know. Great series regardless!
posted by edd at 7:02 AM on May 4, 2012


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