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Space Science

Star Falls Into Black Hole 169

thodelu writes with news that astronomers recently got a look at what they believe is a star falling into a black hole. Phil Plait explains: "As the star approached this bottomless pit, the side of the star facing the black hole was pulled far harder than the other side of the star, which may have been a million or more kilometers farther away from the black hole. This change in pull stretched the star — this stretching is called a 'tide,' and is essentially the same thing that causes tides on the Earth from the Moon’s gravity and when the star wandered too close to the black hole, the strength of that pull became irresistible, overcoming the star’s own internal gravity. In a flash, the star was torn apart, and octillions of tons of ionized gas burst outward! This material whipped around the black hole, forming a disk of plasma called an accretion disk. Magnetic fields, friction, and turbulence superheated the plasma, and also focused twin beams of matter and energy which blasted out from the poles of the disk, away from the black hole itself. The energy stored in these beams is incredible, crushing our imagination into dust: for a time, they shone with the light of a trillion Suns!"
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Star Falls Into Black Hole

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  • by Anonymous Coward on Friday April 08, 2011 @04:14PM (#35763112)

    Why is Slashdot covering Charlie Sheen now?

    • by Tablizer ( 95088 ) on Friday April 08, 2011 @04:17PM (#35763144) Journal

      Dammification! You beat me by one minute. Now my Sheen joke will join the black hole of /. moderation

      • Re: (Score:1, Funny)

        by Anonymous Coward

        Duh, winning. The tiger blood running through my veins allowed me to first post.

    • by Anonymous Coward

      Yeah, and quit ragging on Detroit. They've suffered enough already.

  • To read more about Pia being dumped from American Idol

  • Fitting though, for the death of a star.

    Get his man a turtleneck, joint, and a public television slot!
    • by ackthpt ( 218170 )

      Fitting though, for the death of a star.

      Get his man a turtleneck, joint, and a public television slot!

      It's all relative, man. The star doesn't die, it ceases to be its own entity and combines with the mass of the Black Hole.

      billyuns and billyuns

    • by Opyros ( 1153335 )
      Well, one of the reviews of his latest book does say "Reading this book is like getting punched in the face by Carl Sagan." (quoted on the sidebar of TFA). You're not the first to compare Plait to Sagan.
  • by nebaz ( 453974 ) on Friday April 08, 2011 @04:20PM (#35763168)

    I would be quite surprised if one was able to witness the entire event through a telescope from start to finish. I'm curious how long it takes a star to "fall into a black hole" from start to finish.

    • by Anonymous Coward

      Its all relative.

    • Re: (Score:3, Insightful)

      by barrtender ( 1930830 )

      Unfortunately I think the only signs we got were x-rays, not anything visible.

      As for the duration - there's a couple answers. From our perspective the best I can tell is 41 hours from the note on this picture [swift.ac.uk] saying it was a 41 hour exposure.

      From the sun's perspective it should take forever if I remember relativity right. Someone with more knowledge can correct me here, as I'm not positive and would like to know more.

    • Didn't you read the summary? It happened "in a flash"! No need to read the article for anything more detailed or scientific.

    • by kinnell ( 607819 )

      As I understand it, it would take an eternity from our point of view for the star to fall in the black hole completely due to the time dilation in the vicinity of the black hole. However, I believe what they're seeing is just the start of the event. A star is effectively a huge nuclear explosion kept in equilibrium by a massive gravitational field. As the star approached the black hole, the gravitational field from the black hole would gradually reduce that of the star on the near side until at some poin

    • The description is a bit sensational: star stretched by the enormous tides of the black hole, huge jets of matter, etc... So then you have a look at the actual pictures from the telescope, expecting some spectacular video: hey, see that bright spot? That's it! Sure, I suppose the theory is all correct, but the description would make you believe that they actually saw this happening. Nope.
  • Inexplicably, no witty comment comes to mind.
    • by Anonymous Coward

      Inexplicably, no witty comment comes to mind.

      Apparently you had little imagination to begin with...

    • Inexplicably, no witty comment comes to mind.

      It's Friday; save your wit for Monday when everyone's reading.

  • Gravity... (Score:4, Insightful)

    by ackthpt ( 218170 ) on Friday April 08, 2011 @04:22PM (#35763188) Homepage Journal

    Is a distortion of both Time and Space.

    While a star being stretched and pulled into a Black Hole, and perhaps giving out a death cry (rather poetically written as: "The energy stored in these beams is incredible, crushing our imagination into dust: for a time, they shone with the light of a trillion Suns!") is certainly fascinating stuff. It seems to me that within its own reality the Sun remains unstreched, unbent and happy as can be until it merges with that which is the black hole (which itself is converting matter to energy, emitted from its poles.)

    • Re:Gravity... (Score:5, Informative)

      by mmcuh ( 1088773 ) on Friday April 08, 2011 @04:29PM (#35763252)
      No, the tidal effects exist for any observer.
    • No, tidal forces literally do rip the star apart as it approaches the black hole. It would be torn to its constituent atoms long before it ever got near the event horizon.
      • by ackthpt ( 218170 )

        No, tidal forces literally do rip the star apart as it approaches the black hole. It would be torn to its constituent atoms long before it ever got near the event horizon.

        Usually, and what I'm seeing described in the article, is that the gas from the star is pulled from it, which isn't too unusual where one large star with low density orbits a higher density star with greater mass. Energy emitted from the poles is only from the Black Hole itself, not the star being drawn in - likely the matter from the star will eventually contribute to that stream, though - as pole and disc are quite different locations.

      • Can't help wondering: Does the Department of Transportation put warning signs at the event horizon? Actually, there should be a bunch of them. "Warning, event horizon, .1 light year ahead."

  • Has anybody figured out why this was a part of discover's bad astronomy blog?
    • Re: (Score:2, Funny)

      by Anonymous Coward

      Wild stab in the dark here on that one, 'cause the guy who writes the blog is a professional gamma-ray astronomer, maybe?

  • by GameboyRMH ( 1153867 ) <gameboyrmh@@@gmail...com> on Friday April 08, 2011 @04:36PM (#35763324) Journal

    That's OVER 9000 times the force of 1000 suns!

  • Is this a rhetorical phrase like ginormous, or is this number actually defined somewhere?

    • by tvsjr ( 242190 )

      10^27. Is your Google broken?

    • It's powers of a million, so 1000000^8 or A thousand trillion trillion, a billion billion billion: 1 followed by 27 zeros, 10^27.

      One octillion [wolframalpha.com].

      • It's NOT powers of a million, that's long scale numbers (which has octillion as 10^48, aka 1000000 (10^6) ^8).

        It's powers of 1000, times 1000 to put million at 1,000,000: 1000 * 1000^8 or 1000^(8+1).

    • http://en.wikipedia.org/wiki/Octillion [wikipedia.org]

      Was that really so hard?

      • Must I rely on Google searchs and Wikipedia for all my answers? I've read hundreds of scientific sources and this is the first time I've ever come across Octillion.

        Maybe, simply finding something somewhere on the internet is not enough to make it remarkable.

        • I learned that word in grade school math, before the Internet.

          Maybe, simply finding something somewhere on the internet is not enough to make it remarkable.

          If a word for a mathematical concept isn't "remarkable", then your nickname isn't very appropriate, is it?

        • Must I rely on Google searchs and Wikipedia for all my answers?

          Safer to rely on Google and Wikipedia for all of your answers than to rely on Slashdot for any of them!

    • by ackthpt ( 218170 ) on Friday April 08, 2011 @04:47PM (#35763434) Homepage Journal

      Is this a rhetorical phrase like ginormous, or is this number actually defined somewhere?

      An Octillion is 1,000 Septillions.

      A Septillion is 1,000 Augustillions.

      An Augustillion is 1,000 Julytillions.

      A Julytillion is 1,000 Junetillions.

      A Junetillion is 1,000 Maytillions.

      A Maytillion is 1,000 Apriltillions.

      An Apriltillion is 1,000 Marchtillions.

      And a Marchtillion is 1,074 Februarytillions (except every 4 years when it's exactly 1,000 Februarytillions.)

      Next time look it up in Googol.

    • by mevets ( 322601 )

      | Is this a rhetorical phrase like ginormous
      Does a neologism shit in the woods?

  • by Culture20 ( 968837 ) on Friday April 08, 2011 @04:38PM (#35763348)
    You lose, Sentry! Trillion suns beats a million!
  • by UncleTogie ( 1004853 ) on Friday April 08, 2011 @04:38PM (#35763352) Homepage Journal
    As I was thinking about black holes the other day, a few questions came to mind. I'm no astrophysicist, so pardon if they're silly.

    The setup: If you pass the event horizon, you're going in, obviously. While you won't take forever to hit the singularity once you're past the event horizon, it APPEARS as such.

    1. If I took a cube 100 meters on a side, carved information on it that could be read from a distance, and slung it past the EH, how long would it remain visible? Forever? For the life of the singularity?

    2. If for a long period of time, could this be used as a method of "permanent" information storage? I've read too much sci-fi, as I keep picturing an intergalactic bulletin board... just waiting to be read...

    4. If the block DOES remain visible, and the singularity eventually has enough dropped blocks into it, would it render the black hole "visible"?
    • Re: (Score:2, Informative)

      by Anonymous Coward

      carved information on it that could be read from a distance, and slung it past the EH, how long would it remain visible?

      It wouldn't be visible once it passed the event horizon. That's the defining characteristic of a black hole's event horizon: nothing escapes, including light.

      • Ah, but from an outsider's frame of reference, it would take the block forever to reach the event horizon. On the other hand, the light from the block would get redder and dimmer until it becomes effectively invisible. Remember, relativity means that time and space are relative, so you must always consider the observer's frame of reference.
      • It wouldn't be visible once it passed the event horizon. That's the defining characteristic of a black hole's event horizon: nothing escapes, including light.

        True, but the view of it in it's last instants before it crosses the event horizon would take longer and longer to reach the observer and become increasingly red shifted. It will appear to get closer and closer to the event horizon but never reach it while it fades away as the number of photons reaching the observer are fewer and fewer and are increasi

        • by Kagura ( 843695 )

          True, but the view of it in it's last instants before it crosses the event horizon would take longer and longer to reach the observer and become increasingly red shifted.

          It doesn't take longer and longer to reach the observer, it reaches the observer at the same speed, which is the speed of light. It loses energy, instead, becoming red-shifted.

    • by ackthpt ( 218170 )

      Remember, anything you "Read" is from reflected light. Ain't that a pretzel of the mind?

      • So as soon as it enters the event horizon, poof? No more visible cube (as the reflected light rays are unable to escape)?
        • Comment removed based on user account deletion
        • Re:Silly question: (Score:5, Informative)

          by MoralHazard ( 447833 ) on Friday April 08, 2011 @08:08PM (#35764610)

          NO, absolutely not. An outside observer sees time "slow down" for objects that are approaching a black hole, so that each falling object approaches the event horizon asymptotically BUT NEVER ACTUALLY REACHES IT.

          If you watched somebody falling into a black hole, and you kept a telescope trained on his wristwatch, you would see the second hand sweep slower and slower as he got closer to the EH distance. No matter how long your wait, you'll never actually see anything cross the EH from the outside.

          (I am not kidding, this is what actually would happen. If this seems unpossible, don't worry too much--unless you've already studied special relativity and grasped at least that much, this is pretty counter-intuitive.)

          • Re: (Score:3, Interesting)

            by Anonymous Coward

            No matter how long your wait, you'll never actually see anything cross the EH from the outside.

            Not to burst your bubble or anything, but if nothing ever appears to cross the Event Horizon from an outside perspective then everything that has ever fell in would still look as though it hadn't. All the fallen objects would appear to be continuing to circle the black hole just like everything else in the universe appears to be doing. This could quite possibly, if not probably, mean we have all already passed the Event Horizon of a black hole and are on the inside looking out, rather than the outside looki

            • by sjwt ( 161428 )

              Crossing and Reaching are not the same.
              http://en.wikipedia.org/wiki/Zeno's_paradoxes [wikipedia.org]

            • but if nothing ever appears to cross the Event Horizon from an outside perspective then everything that has ever fell in would still look as though it hadn't. All the fallen objects would appear to be continuing to circle the black hole just like everything else in the universe appears to be doing. This could quite possibly, if not probably, mean we have all already passed the Event Horizon of a black hole and are on the inside looking out, rather than the outside looking in.

              Believe it, man, I shit you not-

          • >>so that each falling object approaches the event horizon asymptotically BUT NEVER ACTUALLY REACHES IT.

            To be fair, there's a certain amount of "open question" about what actually would happen if you threw a baseball into a black hole, as we don't actually have one on hand to play with. There's something of a paradox involved as well, since the baseball (from its perspective) would pass through the event horizon just fine, but observers would watch it stop, or perhaps get smeared across the surface of

    • Comment removed based on user account deletion
      • You see, from your perspective the cube would never quite reach the EH and would appear frozen in time. However, yon cube will sail uneventfully through the event horizon and in short order strike the singularity. This is a paradox, and we all know that any theory which results in a paradox is by definition false.

        Wouldn't it only be a paradox if the cube physically existed in both places? Observation being relative due to dilation and all.

        sail uneventfully through the event horizon

        *rimshot*

      • Sorry, this doesn't make sense to me. The event horizon surrounds the singularity. It is defined as the distance where, once an object is less than that distance from the singularity, no information will ever breach the event horizon again. This applies even to photons; the reason a singularity is called a "black hole" is because once light crosses the event horizon it will never return, giving the effect or an object with absolutely no albedo.

        In other words, once something passes the event horizon, you *ca

        • You have this all backwards WRT how time dilation affects the two frames of reference:

          1) The observer falling into the black hole experiences the trip to the event horizon *normally*. In a finite amount of time, this moving observer will cross the event horizon and reach the singularity--or, at least, his constituent subatomic particles will (tidal force). Crossing the EH is a non-event, for this guy--if the black hole is massive enough, he won't even notice the tidal forces until well after he pass

          • by Jeremi ( 14640 )

            The suicidal (now moving) observer checks his watch about an hour later and measures his distance to his ship: ~1,000 km from his ship (also 1,000 km from the singularity,

            Assuming he manages to withstand getting torn to shreds for long enough, can our suicidal observer look backwards (away from the black hole) and see the entire future of the universe (or much of it) play out in front of his eyes over the next few seconds/minutes of his subjective time?

            That might almost make it worth the trip.

            • Re:Silly question: (Score:5, Informative)

              by Altrag ( 195300 ) on Saturday April 09, 2011 @01:15AM (#35765722)

              No he wouldn't. He looks back and sees the stationary guy 1000km away, but the light took a certain amount of time to get to him, negating any possibility of seeing the "future". The further out into the universe he looks, the further back in time he looks -- the same as happens to us when we stare really far into the sky from Earth -- if we're looking at something 1000 light years away, we know that it happened 1000 years ago (or more, if something managed to slow down the light for part of the journey). We can NEVER see the future (or for that matter, the present). Even reading this on your screen is old news by a tiny fraction of a second as the light moves from your screen to your eye.

              Basically from the moving observer's perspective, nothing unusual is happening at all until the tidal forces kick in.

              As he gets closer and closer to the singularity the tidal forces would rip him into atoms, then the atoms get ripped apart layer by layer until you end up with individual quarks (and who knows what it means to rip a quark or an electron apart.. ie: what happens when space is so warped that a signal can't make it from one side of a quark to the other without exceeding c.)

              All that said, the stationary observer would NOT see the moving guy forever. As others have noted, along with seeing him slow down indefinitely, we'd also see him redshift indefinitely. Eventually he'd be so redshifted that he'd no longer be detectable by the instruments of the stationary observer. He'd still "be there" but could no longer be seen. A more sensitive instrument could see him for a longer period of time, but he'd still fade out eventually as all instruments no matter how good will have a finite cutoff for what they can detect.

        • by slew ( 2918 )

          Well, sortof...

          I'm not certain what will happen to light trying to travel directly away from the singularity from a point outside the event horizon - it might get distorted somehow...

          The light will get redshifted (move towards lower frequency)...

          As I understand it, an outside observer can (relatively) easily calculate the time it will take for the object to reach the singularity...

          Relativistically calculating, the outside observer notes that it takes forever for the object to reach the singularity. Of cour

    • by Tynin ( 634655 )
      My woefully lacking formal education in this area might be showing as well, but let me try to answer:

      1. My understanding is the event horizon is a mind boggling bad place to be near. Even if the spaghettification [wikipedia.org] of your cube didn't take place, light is falling into the black hole, so you'd not be able to read anything in it.

      2. As best we can tell, only Hawking radiation [wikipedia.org] is capable of escaping a black hole. Any information would be lost due to entropy, you'd not be able to retrieve any specific inform
    • Actually, the moment it slung past the event horizon, any light originating from the object would also be trapped within. So, not visible at all.

      Permanence would be lightspeed exactly at the horizon. Still no information getting out though. Very insidious backup system, as the hole slowly absorbs stuff, grows, and eats your data.

      And for things farther away, its just an orbiting billboard, but there are a lot of safer things to orbit than a black hole :]

      I'm not an astrophysicist either, but even if I were, I

    • No, from the outside it will look like the cube just falls in, depending on the size of the black hole and the angle of approach, we may see it undergo spagettification first.

      However, you can use a black hole for data retention as a delay line. There is a distance above the black hole that is called the "photon sphere" which is the point that the orbital speed exactly equals the speed of light, meaning that photons injected at the proper angle will actually be in orbit around the black hole.

      So, you can use

    • by Jeremi ( 14640 ) on Friday April 08, 2011 @09:01PM (#35764830) Homepage

      If I took a cube 100 meters on a side, carved information on it that could be read from a distance, and slung it past the EH

      You euthanized your faithful Companion Cube more quickly than any test subject on record. Congratulations.

    • It would become redshifted and dimmed. Eventually, it would be too dim to see. If it is a radio transmission, the transmission will slow down to a near halt. If it is a tablet, it would be flattened and distorted.

    • The way I see it, you have a limited number of photons striking the cube before it crosses the event horizon. Once the object crosses the event horizon then the photons striking it would also cross the event horizon. These limited number of photons (pre-event horizon) which at first were striking your eyes at a regular pace get slowed down and less and less are hitting your eye per time period.

      Thus, per my understanding, the object becomes dimmer as time passes.

  • the ori are dialing a super gate

  • by Anonymous Coward

    First there were dupe stories and now we get news from billions of years ago, what is /. coming to?

  • I just have one question for the black hole, what did it taste like? And is tabasco required or is it spicy enough on its own?
  • by cvtan ( 752695 ) on Friday April 08, 2011 @05:29PM (#35763800)
    Any site that "embiggens" images when you click on them is OK with me.
  • See? The star didn't believe in his Noodly Holyness, so the Spaghetti Monster slurped it down with great vengeance and furious anger.

    Repent, human heathens, before we are all turned into tomato sauce!

  • by guttentag ( 313541 ) on Friday April 08, 2011 @06:31PM (#35764164) Journal
    I was intrigued by the summary until I read this:

    "The energy stored in these beams is incredible, crushing our imagination into dust..."

    Black hole = awesome. Black hole swallowing a sun = probably beyond the scope of our comprehension, but not quite so amazing that it can turn an intangible thing like imagination into a tangible thing like dust. The author of the summary may have had his brain turned to dust, but to make a claim like this indicates that the imagination is functioning quite well. Perhaps too well.

    • by Kufat ( 563166 )

      Are you demanding the revocation of the author's poetic license?

    • If imagination is intangible, like say, energy, then it can be converted into something tangible, like matter (dust).

      There is in fact a well known formula for this conversion, but as is also well known, the amounts of energy required are vast.

      The Author of the article is pointing out that there is sufficient amount of energy stored in these beams to in fact turn your imagination into dust.

  • Man that really sucks!!! Stars that fall down and can't get back up.

  • Imagine a beowulf cluster of those ...

  • Obligatory Niven (Score:4, Insightful)

    by Nom du Keyboard ( 633989 ) on Friday April 08, 2011 @10:20PM (#35765156)
    If you want to understand the tidal gradient around a very dense object, go read Larry Niven's Neutron Star.

    And you shouldn't have had to scan down 123 postings to find this. /. is slipping.
  • ...will be called "A Star is Torn" ... and the climax will be when the "twin beams of matter and energy which blasted out from the poles of the disk" cross over each other, causing the black hole to explode "into torrents of melted marshmallow".

  • Just like a nuke bomb but maybe a trillion trillion times more powerful, I wonder if ripping a star apart like that is something that gives enough energy to do something incredible with, such as in this case close a black hole...or in some other cases cause rifts in space ...of course this is just theory as no one can know for sure, but when something like this happens, and is recorded, I hope we have the intellect to think that the aftermath is also just as important, to see what else gets affected, from t

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