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Massive Black Hole Devours Star
H3xx writes "Astronomers have observed a black hole shredding a star and sending a powerful beam of energy toward Earth. When it was first observed on March 28th by the Swift spacecraft, it was thought to be the implosion of an aging star, but is now believed to be the result of a star wandering too close to a black hole, imploding and converting 10% of the star's mass into gamma radiation. The energy burst is still visible by telescope more than two-and-a-half months later, the researchers report in the journal Science."
From TFA:
But this event, first spotted on 28 March 2011 and designated Sw 1644+57, does not have the marks of an imploding sun.
More like it got ripped apart. Shredded. As TFA's headline said.
The summary confused me, since pulling mass away from a star would remove the mass that contributes to implosion (which occurs when the continuous explosion within it slows to where it can't keep the star inflated enough and the density gets low enough for implosion to begin, leaving a neutron star or a black hole). But TFA straightened it out.
Neither. It's a relative term -- the black hole in question is the black hole at the centre of a galaxy. I've not read the Science article (I've only read the abstract) so they've not put numbers on it, but it'll be thousands and thousands times the mass of the Sun. A black hole which isn't massive would be up to maybe ten times the mass of the Sun.
How far away is this spectacle? Aren't gamma rays harmful?
This happened almost four billion years ago. :-/
Will we also get a Packt Publishing book on some drupal extension called "Black Hole" as well? That would be the trifecta!
Black Hole: Me eat star! *omnomnom*
Star: *gurk*
Pics or it didn't happen!
FTFA:
the star becomes elongated, first spreading out to form a "banana shape" before its inner edge - orbiting faster than the outer edge - pulls the star into a disc-shape that wraps itself around the hole.
At this point, can fusion even occur at the core of the star? If not, can it even be considered a star once it's matter has been wrapped around a black hole? At what point do we stop referring to it as a star and just consider it part of the black hole's accretion disk. I suppose it really doesn't make a difference what it's called though, since it won't be around for very long.
If what I just said sounded like a troll, it was probably just a failed attempt at humor.
Some cool, news for nerds!
I dunno, I'd imagine it'd be a bit spicy....
Thank you, thank you, I'll be here all week! Try the Betelgeuse, it's to die for!
Monstar L
Black Hole: Star, What's your favorite color?
Star: Red no Yellow no Blue no Black? aaaaaaaaaaaaaaaaaaaaaaah
...quicker, easier, more seductive the darkside is...but more powerful, it is not.
I'm still looking for diligent answer to my StackExchange question: http://physics.stackexchange.com/questions/8294/how-much-of-a-star-falls-into-a-black-hole
Arbitrary masses for the star and black hole should be fine, as you should be able to obtain a percentage of the star that is "DEVOURED!!11" and then create a line chart of the behaviors of stars and black holes with varying masses.
This seems important just to know, but also to make predictions for the Black Hole model.
Then again, I'm too dumb to answer my own question, so what do I know? :)
Omnomnom and omnomnomnom are onomatopoeic words for the sound of one gobbling up something.
That is all.
"sending a powerful beam of energy toward Earth."
Perhaps I'm being pedantic about word choice here - surely a first for /. - but a "beam" of energy implies to me that the energy is narrow and focused, and that description made me think that something came out aimed at Earth (though not, of course, by any deliberate agency.) The original article uses the word "burst" which seems far more appropriate for the kind of energy release its talking about.
"No ads? Kwel!"
click...
"WTF!! My eyes!!!! rip.... them.... OFF!!"
Perhaps I'm trolling, perhaps I'm not.
I'm sure the people spending years programming supercomputers to model supernovae will be fascinated to hear your ruminations. Not sure they'd agree with them, though...
Just a few thoughts in reply:
Not every star goes supernova. In fact, supernovae are really very rare. Most stars have a less violent end. Our own sun, for example, is never going to go supernova but is likely to become a planetary nebula and look quite beautiful to a civilisation a few tens of light years away.
Even if this star would be massive enough to go supernova, why would you assume that tidal stresses would cause a supernova? Or that you can trigger a supernova like that? Supernovae happen when the core of the star is basically made out of iron and it stops burning; the envelope then collapses under gravity and bounces, dramatically and catastrophically. A star that isn't at that stage isn't going to go supernova regardless of what stresses you put it through.
A supernova spits out a lot of gamma radiation, that's true. It also spits out a hell of a lot of other radiation -- and it's pretty characteristic, too. We know what the spectra of different types of supernovae look like and we know how the light-curves evolve over time. If this was a star going supernova we could tell, even if it were falling into a black hole at the same time.
And theoretically, it's possible for a star to become elongated and stretched. Consider a much less brutal example -- a red giant being orbited by a smaller orange star. There's something called a "Roche lobe" which is basically defines where the star's gravity dominates. That means that something within the Roche lobe of one star it's bound to that one, while if it's within the Roche lobe of the other it's bound to *that* one. But if the stars get close enough, there's a point where the Roche lobes meet -- and the two lobes elongate to touch one-another. The giant can then expand, as giants are wont to, and fill its Roche lobe. It takes on an elongated form (and a small stream of matter spirals into the other star). A slightly more dramatic version of this is when a star is orbiting a neutron star; given enough material flowing from the elongated companion onto the neutron star and you *do* trigger a supernova... but it's of the neutron star and not the companion.
That wasn't meant to be as arsey as it sounds, by the way.
You apparently have a right-spin dryer.
These are known to reverse the polarity of left socks, converting them to right socks.
To correct this, you must manually spin the dryer the opposite direction exactly half the number of rotations.
This will reverse the polarity of half the socks back to left socks.
Down With Slashdot BETA!!! I've been around the corner and seen the oliphant; you can only abuse me from your perspecti
The tidal force relieves the gravitational pressure on part of the star, putting out fusion right there.
Is the loss of fusion pressure going to allow that region to collapse on itself enough to super-nova? Or is the tidal force now great enough to keep it from collapsing to that density? Or was the fusion pressure itself causing fusion in a region that couldn't attain the density without the shockwave?
I think most of the star continues to fuse until it's so close it couldn't fuse if it tried. Anything that stops fusing just gets pulled farther away.
If it did go supernova, it would be extremely assymetric. It's no longer a collapsing sphere; it's an egg or ellipse with a part inside the stretched end(s) exploding next to a black hole with an active fusion reaction going on too. It should actually release a lot less energy than a supernova of a star of the same size, as it would happen more slowly and consume less of the total mass. It'd be a small supernova inside an active star.
There's probably some range of masses for which that happens. No way to rule it out from here. And then figure in the warping of spacetime from being that close to a black hole, which may be spinning, too.
I personally dont believe that its possible for a star to be "elongated" and stretched..
If a star can contort itself into odd shapes, what makes you think a black hole can't stretch one out of shape?
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
Not really big news as in major political events but things like this I find fascinating. Extremely large objects doing something that covers a noticable portion of the galaxy (fortunately our solar system is quite far away or we'd all be toast, literally). It kind of makes you wonder of the vast amount of energy involved, how did it all began and where will it end. Meanwhile all you and me puny earthers bitch and moan of all kinds of crap that really don't impact much beyond the surface of this third rock in space.
mfwright@batnet.com
So they've finally found a Black Hole Sun?
If your children ever found out how lame you are, they'd murder you in your sleep
I'm assuming this this powerful beam of energy is an alien transmission which roughly translates to " You're next. "
Astrophysics people have definitions of different black hole classes, judged by their mass. There is a range of masses that have no superlative attached, micro black holes (which I think are only theoretical at this point), massive and super massive. I'm not sure what the ranges of each class are (wikipedia will help you there, no doubt), and there may be more classed than the four I've just listed, but to someone who knows a little more astrophysics than I the word "massive" tells them that this object is bigger than a certain mass but not massive enough to be in the "super massive" class. IIRC the massive and super massive types are usually found in the centre of galaxies.
ULTIMATE vor (the universe episodes)
That wasn't meant to be as arsey as it sounds, by the way.
Not arsey at all, IMHO.
Thanks for a succinct and highly informative post. :-)
..Mullah or Pope, Preacher or Poet, who was it wrote: "Give any one species too much rope and they'll fuck it up"?