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Powerful Supernova May Be Related To Death Spasms of First Stars

Zonk posted more than 7 years ago | from the we-need-a-few-more-heavy-elements-out-here dept.

Space 136

necro81 writes "The New York Times is reporting on a discovery from a team of UC Berkley researchers, who may have discovered the brightest stellar explosion ever observed. Observations of the cataclysmic explosion of a 100- to 200-solar-mass star began last September, based on data from the Chandra X-ray Observatory. The researchers believe that the explosion is similar to the death spasms of the first stars in the universe. The super-massive star's collapse is believed to have been so energetic as to create unstable electron-positron pairs that tore the star apart before it could collapse into a black hole — seeding the universe with heavier elements."

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Black hole (1)

Mipoti Gusundar (1028156) | more than 7 years ago | (#19036781)

We were having one fine black hoal in old Calcultta!

Time-lapse video? (1)

G27 Radio (78394) | more than 7 years ago | (#19036791)

Is there a time-lapse video of this somewhere? The article I read only had an artist's rendering. Or when they say "observed" are they just talking about measurements?

Re:Time-lapse video? (5, Informative)

ls -la (937805) | more than 7 years ago | (#19037119)

As far as I can tell from the articles, most of the observation was through means other than the optical spectrum pictures you're looking for (e.g. x-ray and IR pictures, spectroscopy, etc.). In fact, this supernova was so far away (240 million light years) that I'm not sure they could see it through optical telescopes. Most of a supernova's radiation (especially in something this violent) is emitted in the gamma ray range.

Re:Time-lapse video? (5, Informative)

$RANDOMLUSER (804576) | more than 7 years ago | (#19037711)

Indeed. The best images are from the Chandra [harvard.edu] X-ray observatory. They have some animations here [harvard.edu] .

Re:Time-lapse video? (1)

thewils (463314) | more than 7 years ago | (#19039287)

I really like the 'camera-shake' introduced to the animation. Real Star Trek stuff there :)

Re:Time-lapse video? (3, Informative)

p_trekkie (597206) | more than 7 years ago | (#19037795)

Most of a supernova's radiation (especially in something this violent) is emitted in the gamma ray range.


Actually, most of the radiation comes out as neutrinos. Only 1% comes out in forms we can detect at all...

Re:Time-lapse video? (1)

MollyB (162595) | more than 7 years ago | (#19038867)

"Actually, most of the radiation [from supernovae] comes out as neutrinos. Only 1% comes out in forms we can detect at all..."

Not pretending to be anything but an interested layperson, but how does your response square with this excerpt from Wikipedia [wikipedia.org] ?

Type I versus Type II

A fundamental difference between Type I and Type II supernovae is the source of energy for the radiation emitted near the peak of the light curve. The progenitors of Type II supernovae are stars with extended envelopes that can attain a degree of transparency with a relatively small amount of expansion. Most of the energy powering the emission at peak light is derived from the shock wave that heats and ejects the envelope.[57]

The progenitors of Type I supernovae, on the other hand, are compact objects, much smaller (but more massive) than the Sun, that must expand (and therefore cool) enormously before becoming transparent. Heat from the explosion is dissipated in the expansion and is not available for light production. The radiation emitted by Type I supernovae is thus entirely attributable to the decay of radionuclides produced in the explosion; principally nickel-56 (with a half-life of 6.1 days) and its daughter cobalt-56 (with a half-life of 77 days). Gamma rays emitted during this nuclear decay are absorbed by the ejected material, heating it to incandescence.

As the material ejected by a Type II supernova expands and cools, radioactive decay eventually takes over as the main energy source for light emission in this case also. A bright Type Ia supernova may expel 0.5-1.0 solar masses of nickel-56,[58] while a Type Ib, Ic or Type II supernova probably ejects closer to 0.1 solar mass of nickel-56.
Thanks in advance for advancing my understanding. Apologies if there is anything akin to an apples/oranges misunderstanding at the base of my query...

Re:Time-lapse video? (2, Informative)

p_trekkie (597206) | more than 7 years ago | (#19039729)

Type I versus Type II

A fundamental difference between Type I and Type II supernovae is the source of energy for the radiation emitted near the peak of the light curve. The progenitors of Type II supernovae are stars with extended envelopes that can attain a degree of transparency with a relatively small amount of expansion. Most of the energy powering the emission at peak light is derived from the shock wave that heats and ejects the envelope.[57]

The progenitors of Type I supernovae, on the other hand, are compact objects, much smaller (but more massive) than the Sun, that must expand (and therefore cool) enormously before becoming transparent. Heat from the explosion is dissipated in the expansion and is not available for light production. The radiation emitted by Type I supernovae is thus entirely attributable to the decay of radionuclides produced in the explosion; principally nickel-56 (with a half-life of 6.1 days) and its daughter cobalt-56 (with a half-life of 77 days). Gamma rays emitted during this nuclear decay are absorbed by the ejected material, heating it to incandescence.

As the material ejected by a Type II supernova expands and cools, radioactive decay eventually takes over as the main energy source for light emission in this case also. A bright Type Ia supernova may expel 0.5-1.0 solar masses of nickel-56,[58] while a Type Ib, Ic or Type II supernova probably ejects closer to 0.1 solar mass of nickel-56.
Thanks in advance for advancing my understanding. Apologies if there is anything akin to an apples/oranges misunderstanding at the base of my query...

The answer lies in whether you count neutrinos as radiation or not. What I should have stated in my original post was that the vast majority of the energy released in supernoave comes out in the form of neutrinos, which we have a really really hard time detecting...

Wikipedia is correct as to the source of photons that we detect. I counted neutrinos as a form of radiation in my earlier statement (since in my mind, that's what they effectively are), but neutrinos are not photons. Hence, there is no discrepancy. Basically, when we take the energy difference between the potential energy of a star before and after a Type II SNa (like this one) and check that against the energy we see from photons, we are only seeing 1% of the energy that should be coming out in all forms of light. The rest of the energy is believed to escape in the form of neutrinos.

Re:Time-lapse video? (1)

imsabbel (611519) | more than 7 years ago | (#19039745)

This is attributing the light curve, i.e. the detectable energy emission.
The neutrinos escape the first seconds, long before the weeks the fireball may need to get transparent enough for most radiation.

Re:Time-lapse video? (3, Informative)

imsabbel (611519) | more than 7 years ago | (#19039789)

Also:
"
The core implodes at velocities reaching 70,000 km/s (0.23c),[40] resulting in a rapid increase in temperature and density. Through photodissociation, gamma rays decompose the iron into helium nuclei and free neutrons. The conditions also cause electrons and protons to merge through inverse beta decay, producing neutrons and electron neutrinos. About 1046 joules of gravitational energy are converted into a ten-second burst of neutrinos.[41] These carry away energy from the core and accelerate the collapse, while some neutrinos are absorbed by the star's outer layers and begin the supernova explosion.[42]

The inner core eventually reaches a density comparable to that of an atomic nucleus, where the collapse is halted. The infalling matter then rebounds, producing a shock wave that propagates outward. This expanding shock can stall in the outer core as energy is lost through the dissociation of heavy elements. However, through a process that is not clearly understood, the shock reabsorbs 1044 Joules[a] (1 foe) of energy, producing an explosion.[43]"

You might have stumbled upon this part of the article while getting to the part you quoted. 10^44 joule ->explosion, 10^46 joule -> neutrino burst.
->only 1% is visible.

Re:Time-lapse video? (2, Funny)

Tablizer (95088) | more than 7 years ago | (#19038529)

Is there a time-lapse video of this somewhere? The article I read only had an artist's rendering. Or when they say "observed" are they just talking about measurements?

Be veeery careful when asking for images on slashdot of anything that explodes, bursts, or has holes in it.
     

Re:Time-lapse video? (0)

Anonymous Coward | more than 7 years ago | (#19038735)

I'm not sure how quickly these things unfold, but you generally don't have the luxury of watching it in realtime like a puny little nuclear warhead test. At this distance, even super-powerful explosions like this a fairly faint and require long exposures. The most useful information, however, generally comes from a spectrometer rather than a camera. This doesn't produce an image, but a count of the number of photons received at various wavelengths, which helps astronomers figure out the energy of the explosion. They can backfit those calculations to their computer models of what they think stars do when they explode and either figure out what the star was probably doing just before it exploded, or if it's one they've observed before, use before and after data to refine their understanding and computer models.

Of course, the telescope images aren't useless either. The link another poster provided shows two glowing orbs, indicating this ejected most of it's material along it's spin axis. This was a surprising finding when they first started taking detailed pictures of supernovae, because classical explosions are radially symetric.

In response... (-1, Offtopic)

CdrGlork (1096607) | more than 7 years ago | (#19036815)

After being informed of this, President Bush was quoted as saying, "Can we get ourselves a bomb to do that?"

Kinda OT, but I thought I'd say... (5, Funny)

Red Flayer (890720) | more than 7 years ago | (#19036831)

Great summary. Lots of informative links, accurate and intriguing summary of the article(s). No gratuitous inflammatory question.

Someone pinch me, I think I'm dreaming.

Re:Kinda OT, but I thought I'd say... (3, Funny)

Anonymous Coward | more than 7 years ago | (#19037361)

Look, though! there's an off-topic post!!!

Re:Kinda OT, but I thought I'd say... (1)

MontyApollo (849862) | more than 7 years ago | (#19037549)

Well, to nitpick, the summary could have credited the grad student from Univ. of Texas that made the actual discovery instead of leaving UT out completely.

Re:Kinda OT, but I thought I'd say... (2, Informative)

BlackSnake112 (912158) | more than 7 years ago | (#19037673)

"University of Texas graduate student Robert Quimby first observed the supernova on Sept. 18, 2006 in the galaxy NGC 1260, located in the constellation Perseus. Filippenko's team immediately began observing it with its dedicated supernova search and monitor telescope at Lick, the Katzman Automatic Imaging Telescope." They did, if you RTFA

Re:Kinda OT, but I thought I'd say... (1)

MontyApollo (849862) | more than 7 years ago | (#19037735)

This thread was in reference to the slashdot summary, not TFA. That's why he said it was kinda OT.

Re:Kinda OT, but I thought I'd say... (1)

ebingo (533762) | more than 7 years ago | (#19037759)

He was talking about the summary, if you RTFP

Re:Kinda OT, but I thought I'd say... (1)

Red Flayer (890720) | more than 7 years ago | (#19038141)

Except that the articles were about the research done by the guys at UCal Berkeley who presented some of their findings yesterday.

If the articles had been about the discovery of a supernova, then I'd agree with you -- but they are about the type of supernova it is, and the implications of that -- which was discovered by the UCal Berkeley guys.

Re:Kinda OT, but I thought I'd say... (1)

arbitraryaardvark (845916) | more than 7 years ago | (#19038107)

And it's not a dupe.
Oh, Slashdot has already covered the supernova, back in January.
not a dupe [slashdot.org]
What's new is the mainstream media like the new york times finding out about it.

Re:Kinda OT, but I thought I'd say... (1)

Red Flayer (890720) | more than 7 years ago | (#19038739)

Go ahead and read the articles linked to in the summary, then go back and read the one from January. Same supernova, completely different articles with new information based on new research. Oh, but that would mean you'd have to RTFA, right?

Re:Kinda OT, but I thought I'd say... (1)

imikem (767509) | more than 7 years ago | (#19038349)

Is anyone else saddened that the parent post was modded Funny?

Oddity (3, Interesting)

tomstdenis (446163) | more than 7 years ago | (#19036875)

They talk at the end about a star 7500 LY away that might "go supernova soon." It should probably be pointed out that it could have already gone supernova 6000 years ago and we'd not know about it.

I guess they should say "might see if it went supernova soon."

Tom

Re:Oddity (4, Insightful)

Nos. (179609) | more than 7 years ago | (#19037205)

I think this is getting a bit pedantic. Sure, the light takes 7500 years to get here, thus it could have gone supernova quite some time ago, and the astronomers know this. It doesn't mean we have to speak about everything having occurred in the past... its all relative.

Re:Oddity (1)

Goalie_Ca (584234) | more than 7 years ago | (#19039551)

Just a guess but if you draw the light cones.. it's probably in absolute past.

Re:Oddity (1)

Gilmoure (18428) | more than 7 years ago | (#19040491)

I prefer Smirnoff. Or better yet, Jim Beam.

E.L.E (4, Interesting)

TheSciBoy (1050166) | more than 7 years ago | (#19037393)

What I found interesting was that Eta Carinae apparently behaves the same way as the other star, which begs the question: could we survive the supernova? The explosions of stars certainly are powerful enough to destroy such delicate lives as ours if they are close enough. Question is, is Eta Carinae close enough?

Now that's an Extinction Level Event.

"Ooh! Aaah!" dead

Re:E.L.E (0)

Anonymous Coward | more than 7 years ago | (#19039197)

Raises the question?

Re:E.L.E (1)

Gilmoure (18428) | more than 7 years ago | (#19040607)

Was wondering about that myself. Do we need to start building a scrith ring edge on with Eta Carradine?

Re:E.L.E (2, Interesting)

OldSoldier (168889) | more than 7 years ago | (#19040805)

Yes and no. Astronomers have been wondering about Eta Carinae for awhile. It appears that it can produce "gamma ray bursts" that are powerful enough to wipe out life even here, 7500 light years away, but current thinking is that GRBs are focused events, gamma rays streaming along the magnetic axis of the exploding star and fortunately Eta Carinae's axes are not pointed in our direction.

I'm not endorsing this link http://people.roma2.infn.it/~aldo/dar01.pdf [roma2.infn.it] but it does corroborate what I've heard on TV science shows.

Re:Oddity (4, Insightful)

JesseL (107722) | more than 7 years ago | (#19037455)

Your post is based on the flawed premise that there exists some kind of objective time.

Re:Oddity (2, Informative)

linzeal (197905) | more than 7 years ago | (#19038637)

Also known as, Minkowski Space [wikipedia.org] .

Re:Oddity (3, Informative)

ls -la (937805) | more than 7 years ago | (#19037467)

I guess they should say "might see if it went supernova soon."
We know information cannot travel faster than the speed of light (or if you prefer, cannot reach outside the light-cone [wikipedia.org] of the event). So if an event "happens" 7500 light years away, did it really happen before the light reaches us? In some sense, an event has not happened until we are inside its light-cone.
Perhaps it "happens" when its light-cone intersects ours? The question with this interpretation is, where does our light-cone start?

Time is relative, and over distances of at least the order of a light second (186,000+ miles), it is difficult to think about correctly.

Re:Oddity (1)

AlXtreme (223728) | more than 7 years ago | (#19038111)

So if an event "happens" 7500 light years away, did it really happen before the light reaches us?

How about we ask the 10-legged 8-eyed blue/green alien that got obliterated because his planet was circling that supernova?


Sorry, but these silly smart-sounding 'If a tree in the forest fell, but no one heard it fall, did it really make a sound?'-rhetorical questions irk me. The squirrel on who's head that tree fell doesn't give a crap if it made a sound. Think of the squirrels!

Re:Oddity (1)

mmdog (34909) | more than 7 years ago | (#19039199)

Your post reminds me of a Arthur C. Clarke story called The Star

Just thought I'd take the opportunity to throw that title out there. It's a great story about god and supernovae.

Re:Oddity (1)

DragonWriter (970822) | more than 7 years ago | (#19040605)

How about we ask the 10-legged 8-eyed blue/green alien that got obliterated because his planet was circling that supernova?


Since the time for information from the alien about the supernova to reach us is at least as long information from the supernova itself, that doesn't really change the problem, even ignoring the problem of asking.

Re:Oddity (0)

Anonymous Coward | more than 7 years ago | (#19038561)

Have you seen the size of her cones?

Re:Oddity (1)

Red Flayer (890720) | more than 7 years ago | (#19039451)

We know information cannot travel faster than the speed of light
Do we really? How about spooky action at a distance [csmonitor.com] ? Quantum entanglement enables the transmission of information instantaneously.

Re:Oddity (1)

JesseL (107722) | more than 7 years ago | (#19039643)

Quantum entanglement enables the transmission of information instantaneously.
No, it doesn't.

Pretty much everything I have ever read about quantum entanglement is careful to point out that it does not enable information to propagate faster than light.

Re:Oddity (5, Informative)

Orange Crush (934731) | more than 7 years ago | (#19037535)

There is no such thing as synchronicity in this universe. Cause travels at the speed of light (or slower), gravity and relative velocity alter time and quantum states are ambiguous until observed. That star has a high probability of already having gone supernova, but this is meaningless in our frame of reference until the event is observable.

Re:Oddity (1)

mrcubehead (693754) | more than 7 years ago | (#19038801)

So what do scientists mean when they say quantum entanglement shows particles can instantaneously affect each other over any distance?

Re:Oddity (1)

Orange Crush (934731) | more than 7 years ago | (#19039345)

IANAP, but my understanding is that quantum entanglement only allows two remote observers to see the same thing and it works across space and time. No information passes between the observers. As far as either party is concerned, there's only a probability the other one even saw the entanglement event until they talk about it via light speed.

Re:Oddity (1)

cdrudge (68377) | more than 7 years ago | (#19039097)

but this is meaningless in our frame of reference until the event is observable.
So if I cheat on my wife, until she observes it it doesn't mean anything? Hmmm...

Re:Oddity (1)

Orange Crush (934731) | more than 7 years ago | (#19040285)

So if I cheat on my wife, until she observes it it doesn't mean anything? Hmmm...

Until observed, it's just a probability. However, considering this is Slashdot, I believe the probability of you having both a wife and a mistress is quite low.

Re:Oddity (0)

Anonymous Coward | more than 7 years ago | (#19037877)

This is meaningless. The star might explode soon in our system, in which the "now" of far places is, you might say, in the past.
What I want to know is how soon? Is it probable it will be this year, or in the next hundred? Or do they think it might explode any time in the next million years?

Re:Oddity (1)

JATMON (995758) | more than 7 years ago | (#19039367)

A better way to phrase your question would be to ask "How soon before we see the supernova?" And the answer is that no one knows the exact time. It could happen tomorrow, next year, or hundreds to thousands of years from now. There is no way to get that precise. To guess to within 1000 years would be similar to observing a 99 year old person for a couple minutes. Compare what we observed to what we know from observing other people of similar age. Then calculate, to within a day, when that person will die.

Re:Oddity (2, Insightful)

profplump (309017) | more than 7 years ago | (#19037901)

That's only true if you assume that two distant points share the same timescale -- a relativist might argue that "now, far away" is the same moment in time as "here, long ago", at least baring the discovery of macro-scale faster-than-light causation. That is to say, while an observer near the supernova might have seen the explosion long ago, his "long ago" and your "now" may be the same moment, not just two different perspectives of the same event that happened long ago with respect to all observers.

Beside that, even if there is a universal timescale unrelated to the speed of light, from our perspective it is happening "now", and since we don't often communicate with anyone more than a few thousand miles away it's silly to express things in any other timescale.

Re:Oddity (1)

eharvill (991859) | more than 7 years ago | (#19040237)

"A long time ago in a galaxy far far away..." So we just witnessed Luke taking out the original Death Star??

Re:Oddity (1)

internic (453511) | more than 7 years ago | (#19038291)

Sure, that's a reasonable thing to say. But while we're being pedantic, we could also point out that it's all relative. Since the event of the explosion has a space-like separation from the events occurring on Earth now (e.g. the post), the time ordering of the events is different in different inertial frames of reference [everything2.com] . Thus, it may not have happened yet, or it may already have happened, depending on whom you ask (specifically, what reference frame they're in). Still, I'll grant you that in the instantaneously co-moving rest frame of anybody on Earth right now, it would be correct to say it has probably already happened.

Have we got that all out of our systems now?

Re:Oddity (1)

Gilmoure (18428) | more than 7 years ago | (#19040793)

When will we observe the explosion, here on Ert?

Re:Oddity (1)

inviolet (797804) | more than 7 years ago | (#19039217)

I guess they should say "might see if it went supernova soon."

You should have consulted Dr. Dan Streetmentioner's "Handbook of 1001 Tense Formations". If you had, you would know that the correct way to phrase the idea would be: "might seeon if it golo supernova insooner".

we should we believe the astrophysicists now? (-1, Flamebait)

peter303 (12292) | more than 7 years ago | (#19036929)

After 70 years of computer simulations and observations they failed to predict this new kind of supernova. Its interesting to read speculations about degenerate lepton gases, but arent they just hand-waving again? Just goes to show you the arrogance of physicists- they claim answers and grandiose Standard Theories, but are frequently revising them because they mis things like accelerating expansion and 150SM supernova.

Re:we should we believe the astrophysicists now? (5, Insightful)

Vendetta (85883) | more than 7 years ago | (#19037059)

So you're saying it's a bad thing to revise theories based on new information or observations? There is a reason they are called "theories".

Re:we should we believe the astrophysicists now? (4, Insightful)

PFI_Optix (936301) | more than 7 years ago | (#19037125)

It's the revisions that make it science.

Some scientists--and physicists can be especially guilty of this in my experience--place too much faith in their own knowledge and accept the current findings of science as absulute fact. They forget that science is fluid, always changing as new information enters the equation and each answer spawns new questions. Call it arrogance if you want; I think it's something less than that.

In any case, what's the alternative? "God did it"? That may very well be true, but it doesn't answer the question of "how did it happen?"...which is what science seeks to explain.

Re:we should we believe the astrophysicists now? (1, Interesting)

Notquitecajun (1073646) | more than 7 years ago | (#19037225)

I think this comes close to the problems with scientific debate and creation; one places a definition on "theory" that is far too close to "universal law" (which doesn't particularly exist) and the other defines it far too closely to "hypothesis."

Both, I have found, tend to be far too dogmatic in their beliefs on the debate (or, dare I say it, faith).

Re:we should we believe the astrophysicists now? (0)

Anonymous Coward | more than 7 years ago | (#19037373)

"32 score decades oughta be enough for anybody" -- Genesis 4:11

Re:we should we believe the astrophysicists now? (0)

Anonymous Coward | more than 7 years ago | (#19038003)

This is a great comment that nicely summarizes the scientific method. I may be a bit off-topic, but I wish I could find more comments like this in the anthropogenic global warming debates here on /.

Re:we should we believe the astrophysicists now? (1)

Anonymous Coward | more than 7 years ago | (#19037237)

What, they had supercomputers back in the 1930s? Neutrons were only first discovered in 1932. The theoretical existence of neutron stars wasn't conceived until 1933. The discovery of pulsars didn't happen until the later 60s.

Arrogance would be to say that what they know now is the ultimate truths. Scientific theories are always being re-thought and re-worked. Nobody claims to have all the answers. Sorry, quacks do, but real scientists don't.

Good science provides answers to some fundamental question. In turn those answers will spawn many more new questions. The never-ending quest for knowledge.

I just wonder who the hell modded the parent up? Someone from Kansas, probably.

Re:we should we believe the astrophysicists now? (4, Informative)

Red Flayer (890720) | more than 7 years ago | (#19037241)

Just goes to show you the arrogance of physicists- they claim answers and grandiose Standard Theories, but are frequently revising them because they mis things like accelerating expansion and 150SM supernova.
Right. So we should not put blind faith in any theory, because it's open to being falsified. That's basic scientific method stuff.

Isn't this what academic research is (in theory) all about? The search for better understanding, enabling us to revise our theories of how the universe (or some small subset of it) works?

Find the simplest theory that fits all the observations. New data may mean you need a new theory, or that you need to revise your current theory. I don't understand the problem you have, unless it's just with the arrogance of some theorists who claim to have found the answer to Life, the Universe, and Everything. I say, let them be arrogant -- when they are disproved, they'll fall harder for it.

Re:we should we believe the astrophysicists now? (5, Insightful)

Ambitwistor (1041236) | more than 7 years ago | (#19037349)

Why shouldn't we believe "the astrophysicists"? Did they lie to you? Gore your ox? Steal your candy? Pee in your breakfast cereal?

After 70 years of computer simulations and observations they failed to predict this new kind of supernova.

Yeah, so? There are infinitely many things that are true which scientists have yet to predict. Why are you under the impression that scientists are supposed to know everything? Even if they did know all the physics involved, you can still only make finitely many predictions in finite time.

Its interesting to read speculations about degenerate lepton gases, but arent they just hand-waving again?

"Again"? When were they "hand-waving" before? About what?

Just goes to show you the arrogance of physicists- they claim answers and grandiose Standard Theories, but are frequently revising them because they mis things like accelerating expansion and 150SM supernova.

That's a feature, not a bug. It's how science works! Physicists claim answers because they have answers. That doesn't mean they have ALL the answers, or they're always right. This is no different in astrophysics than in any other field of physics, or any other science, or in any other field of study, period. People know some things, they can predict some things, and sometimes they miss something or get something wrong. That doesn't mean that nobody knows anything or that experts have nothing useful to say.

(By the way, accelerating expansion was in Einstein's theory from the start, but he took it out because there wasn't any evidence for it at the time.)

I seriously don't understand your point of view, unless (as is likely) it's just flamebait. Every time something new is discovered, do you seriously run around disparaging whole fields of science just because the new thing wasn't predicted ahead of time? Or do you just have some bug up your nose about astrophysicists? It's not like they were even wrong about normal supernovae, they just didn't predict this new kind.

Re:we should we believe the astrophysicists now? (1)

roman_mir (125474) | more than 7 years ago | (#19038277)

The GP just fell a victim of the X-Files series, in which Scully would always say something like: "This is science, you do not questions science, god damn it!" (well, ok, I added the 'god damn it' part, but the rest is exactly what the show was about - the rigid and unquestionable science constantly standing in a way of a religios like believe that the Truth is out there.)

Re:we should we believe the astrophysicists now? (2, Insightful)

DrJay (102053) | more than 7 years ago | (#19037375)

Actually, my understanding was that astronomers are suggesting that this may be the first observed case of a type of supernova called pair-instability. The actual prediction of pair-instability supernovae was made decades ago - it's more that observations are catching up with predictions.

So, you seem to have gotten this exactly backwards.

As a bit of reading should also make clear, the reason that observations of this type of supernova are rare is that the conditions that favored the formation of stars capable of exploding this way have become rare as the universe has aged. They are expected to be far more common in the early universe, and it's hoped that the next generation of space telescope will be capable of viewing them (as it will see further, and thus earlier, into the universe).

Re:we should we believe the astrophysicists now? (0)

Anonymous Coward | more than 7 years ago | (#19037667)

If you bothered to read the article, you'd see that the probable cause of the supernova's extreme gamma production actually was predicted some decades ago. It's simply that no-one expected to see a supernova from a star that big, so people mostly forgot about the calculation. Of course, no-one is certain that pair instability is the actual mechanism, it being difficult to perform repeatable tests on a very remote explosion...

In addition, it seems odd that you're expecting people to predict essentially random events occurring in the deep past and (equivalently) hundreds of millions of light-years away. That seems like the domain of soothsayers, not responsible scientists.

(Finally, of course, science also has to progress by the accumulation of evidence, and novel phenomena are part of this. This is especially true in astrophysics, where you can't actually perform experiments directly - you have to do the equivalent of stamp collecting instead.)

Re:we should we believe the astrophysicists now? (4, Insightful)

Hoi Polloi (522990) | more than 7 years ago | (#19037801)

How is trying to explain something based on the best current evidence arrogance? Are you saying people shouldn't ever believe anything or they should just ignore new info? Sorry but science is a continual learning process and unlike religion is constantly adjusting to new information and better explanations.

Re:we should we believe the astrophysicists now? (5, Insightful)

stewardwildcat (1009811) | more than 7 years ago | (#19037911)

As an astrophysicist I feel I should comment. First of all, 70 years of computer simulations later.... we are just beginning to be able to model a supernova with high enough resolution that we can "kind of" fit the observations without contrived scaling factors. This is also only being done in two dimensions and for the first few microseconds of a supernova. Models that hardly include all the physics involved are too much for the modern computational machine. Everytime we run a new model that includes more physics, they fit the data better and better. It is this way we discover what physics matters in the actual explosion. Since we cannot COMPLETELY model anything in real life on a computer all simulations are hand-wavy. Second, developing theories is very important. You use all of the available data and create a theory that can be tested and describes the current state of what you are studying. The real test of a theory is if it stands up to scrutiny. IF the "standard model" was so vague that no meaningful tests could be performed to prove the theory incorrect then it is a bad theory. Scientists prove things wrong, that is out job. We find situations where the current models do not describe the observations. That is scientific progress. We adjust our theories and learn about new physics. If gravity wasnt tested we would still be using Newtonian Gravity rather than General Relativity, which is still being worked on today (Gravity Probe B). Lastly, Astronomers have never observed a 150-200 Msolar supernova before. This is the first time we are able to look at what might have happened when the first stars formed. If we had seen a whole lot of these and had a perfect unified model then we wouldnt have to do science or discover things anymore. This is an exciting time as we have the most advanced instruments built by humans peering into the early universe discivering where we came from. I am always excited about new results, whether they be proven wrong or not, because we are always one step closer to understanding the world in which we live.

Re:we should we believe the astrophysicists now? (0)

Anonymous Coward | more than 7 years ago | (#19038155)

After 70 years of computer simulations and observations they failed to predict this new kind of supernova.

You're right. Mainstream astrophysics is just a bunch of hooey. These guys will eventually be forced to confront the one true theory: the electric universe [slashdot.org] . After all, in the electric universe theory, supernovas are easily explained as...um...well...anyway, it's just a simple electricity-effect-thingy.

Eta Carinae (5, Interesting)

tiluki (74844) | more than 7 years ago | (#19037013)

What is more impressive about this story is the footnote of similar activity recently exhibited by Eta Carinae - a much closer star to us (well, 7500 light years). To quote the BBC article http://news.bbc.co.uk/1/hi/sci/tech/6633609.stm [bbc.co.uk] :

Dave Pooley, at the University of California at Berkeley, said if Eta Carinae were to explode "it would be so bright that you would see it during the day, and you could even read a book by its light at night". Eta Carinae's death could be "the most spectacular star show in history."
Is it just me, or does that sound a little bit too close...

Re:Eta Carinae (1)

CmdrGravy (645153) | more than 7 years ago | (#19037141)

I was interested by that too, it doesn't really say what they mean by soon though which when you're talking about galactic events can mean anything from really soon ( next week ) to in a couple of million years.

Personally I'd love to see this, provided of course that it wasn't the last thing I ever saw, very briefly.

Re:Eta Carinae (4, Informative)

Jugalator (259273) | more than 7 years ago | (#19037193)

It's not too bad unless we'd be unlucky and have a gamma radiation burst from it heading towards us.
From here [freeinternetpress.com] :

The potential danger comes from the fact that explosions of massive stars generally emit jets of intense gamma radiation, among the most powerful and harmful forces in the universe. If Eta Carinae did explode and a jet was pointed in the general direction of the solar system, Livio said, Earth could be endangered. But because the gamma-ray jets tend to be relatively narrow, like the beam of a lighthouse, the odds are that the jet would miss Earth.

So it's not too bad, it would probably just miss us.

:-/

Re:Eta Carinae (2, Interesting)

secPM_MS (1081961) | more than 7 years ago | (#19038335)

Eta Carinae is a Luminous Blue Variable, a very massive star (~ 80 to 120 Msolar) that is quite unstable. Last century it ejected ~ 10 solar masses of material. It is also a binary star, with a companion estimated to be ~ 80 solar masses or so. The orbit is significantly inclined from our point of view, so the spin axis is not pointed at all towards us, which is very fortunate indeed. I seem to remember one article a year or so ago that estimated that Eta Carinae was spinning at ~ 90 % of its breakup speed. This is very fast indeed, and if true, would mean that it would be a potential gamma ray burst source when it goes supernovae. Note that it would have to shed its atmosphere first and become a Wolf Rayet star before the GRB could punch through the stellar atmosphere.

Pair creation supernovae were predicted decades ago. The conditions for their formation are a bit strict and they do not appear to be very common at this point. Black hole creation is probably must more common. If we have seen one now, it is a good reinforcement of old theoretical work.

Re:Eta Carinae (2, Informative)

georgewilliamherbert (211790) | more than 7 years ago | (#19039397)

Pair creation supernovae were predicted decades ago. The conditions for their formation are a bit strict and they do not appear to be very common at this point. Black hole creation is probably must more common.

If you neglect angular momentum (i.e., for only moderately rotating stars), the current predictions are that pair creation supernovae are the normal mechanism for stars with a low metalicity and immediately pre-supernova mass from about 140 to about 260 solar masses. If you look at the webpage in the summary http://astro.berkeley.edu/~soffner/imgsf8.html [berkeley.edu] it shows the metalicity / mass behavior estimates. Also see http://www.ucolick.org/~alex/firststars/ [ucolick.org] , particularly the diagram at the bottom. It shows the no angular momentum low metalicity stellar behavior: 8-25 Solar Masses, you get a neutron star. 25-50ish, you get a neutron star that then reabsorbs enough of the source star's mass via fallback to become a black hole. 50-100, you get a direct collapse to a black hole. From 100 to 130 solar masses, the pair production mechanism kicks in and pulses a few times, ejecting mass, and then it falls below 100 SM from the ejections and should collapse to a black hole on the next pulse. From 130 or 140 up to about 250 or 260 (depends on whose paper/numbers), pair production doesn't pulse, it goes bang, and the explosion generates enough energy to gravitationally unbind the whole star (blow it completely apart, no or little remnant). Above the 250/260 point, they predict that pair production happens but it just direct collapses essentially the whole star to a black hole, not fusions off to explosion as in the slightly smaller ones.

Re:Eta Carinae (1)

Belial6 (794905) | more than 7 years ago | (#19038365)

Wouldn't that just give us all super powers? And if so, what are the odds of getting invisibility as opposed to being turned into a giant green monster that likes to smash?

Re:Eta Carinae (1)

Tablizer (95088) | more than 7 years ago | (#19038479)

explosions of massive stars generally emit jets of intense gamma radiation, among the most powerful and harmful forces in the universe. If Eta Carinae did explode and a jet was pointed in the general direction of the solar system, Livio said, Earth could be endangered.

We don't know whether God "plays dice" with the universe, but we do know that he plays Russian Roulette.

Imagine what would happen if we found the spin axis of Eta pointing strait our way (fortunately, it is not, as others pointed out). Well, at least we would have some warning, unlike lots of other things that could foobar our planet (like mad dictators and mad cowboys with nukes).
   

Re:Eta Carinae (0)

Anonymous Coward | more than 7 years ago | (#19038701)

Awwww. They nearly missed. Poor earth.

Re:Eta Carinae (1)

Detritus (11846) | more than 7 years ago | (#19037213)

I wonder about that every time a scientist is quoted as saying that a particular supernova was as bright as the combined brightness of the other stars in the parent galaxy. What happens to us if that occurs in our corner of the galaxy? I think there has been some speculation that some past mass extinctions on Earth could have been caused by bursts of radiation from sources outside the solar system.

Re:Eta Carinae (4, Informative)

vrmlguy (120854) | more than 7 years ago | (#19037475)

First, Eta Carinae is not visible to anyone north of 27 N, so in the US only people in or south of Miami will see it. In Africa, you basically have to be in a country that doesn't touch the Mediterranean Sea; while in Asia every country touching the Indian Ocean will see it, but not China or Japan. Among English-speaking countries, only Austrailia will have a great view, but the ozone layer will protect them (and the rest of the Southern Hemisphere) from direct radiation. "Scientists at NASA and Kansas University have determined that the supernova would need to be within 26 light years from Earth to significantly damage the ozone layer and allow cancer-causing ultraviolet radiation to saturate the Earth's surface. An encounter with a supernova that close only happens at a rate of about once in 670 million years(...) The new calculations are based largely on advances in atmospheric modeling, analysis of gamma rays produced by a supernova in 1987 called SN1987a, and a better understanding of galactic supernova locations and rates. A supernova is an explosion of a star at least twice as massive as our Sun." [nasa.gov] Since Eta Carinae is 300 times that distance, its blast wound need to be 90,000 times as energetic to be dangerous. A hypernova is about 100 times more powerful than a supernova, so there's plenty of margin of safety there.

Re:Eta Carinae (1)

fishbowl (7759) | more than 7 years ago | (#19038945)

>Is it just me, or does that sound a little bit too close...

I've read by starlight. Haven't most people who are into astronomy? In the light-polluted, air-polluted cities, it's easy to forget how bright the night sky can be, and city dwellers learn to dismiss the value of night vision as they lose it.

Shock and Awe (0, Troll)

farker haiku (883529) | more than 7 years ago | (#19037053)

President Zarlak of the Kharyak Confederation:
For much of the last millenium, Ksharyak's defense has relied on the Cold War doctrines of deterrence and containment. In some cases, those strategies still apply, but new threats also require new thinking. Deterrence, the promise of massive retaliation against Solar Systems, means nothing, against shadowy, terrorist networks with no home planet or citizens to defend. Containment is not possible when unbalanced dictators with weapons of mass destruction can deliver those weapons on missiles or secretly provide them to terrorists' allies. Thus we have started a war plan that we call "Shock and Awe". We believe it is working. We believe that no group will again threaten the sovereignty of the Kharyak Confederation after this display. Even the bastard stepchildren of the universe are aware of our power now.

From the words of a flea bag in the far reaches of the universe:

"Of all exploding stars ever observed, this was the king," said Alex Filippenko, UC Berkeley astronomer and leader of the ground-based observations at the University of California's Lick Observatory in California and the W. M. Keck Observatory in Hawaii. "We were astonished to see how bright it got, and how long it lasted."

Re:Shock and Awe (1)

djasbestos (1035410) | more than 7 years ago | (#19037089)

Kinda makes the Tsar Bomba look like chump change.

Of course. (1)

Opportunist (166417) | more than 7 years ago | (#19038177)

I mean, it's been like a few magnitudes smaller. Gimme about 500 sun masses and I create you something spectacular too!

Compared to this, the Tsar was the equivalent of an ant farting.

Then again, I'm glad it was. Just imagine...

Re:Of course. (1)

djasbestos (1035410) | more than 7 years ago | (#19038567)

Yeah...it kinda makes you feel insignificant, which is nice, in a way.

Boom? (3, Funny)

Jugalator (259273) | more than 7 years ago | (#19037093)

Big badaboom!

Here's the NASA page. (5, Informative)

u-bend (1095729) | more than 7 years ago | (#19037177)

Here's the NASA article about it. [nasa.gov]

Re:Here's the NASA page. (2, Informative)

john83 (923470) | more than 7 years ago | (#19038267)

Here's the paper about it [arxiv.org] .

From the abstract:
We report our discovery and early observations of the peculiar Type IIn supernova SN 2006gy... It is not yet clear what powers the enormous luminosity ... but we argue that any known mechanism ... requires a very massive progenitor star... SN 2006gy is the first supernova for which we have good reason to suspect a pair-instability explosion... SN 2006gy also suggests that the most massive stars can create brilliant supernovae instead of dying ignominious deaths through direct collapse to a black hole. If such a fate is common among the most massive stars, then supernovae from Population III stars in the early universe will be more numerous than previously believed.

Interesting stuff!

It's Berkeley (1)

thib_gc (730259) | more than 7 years ago | (#19037255)

It's Berkeley, not Berkley.

Re:Actually, it's T E X A S (3, Informative)

MontyApollo (849862) | more than 7 years ago | (#19037421)

From the article:

The discovery was made by Robert Quimby, a University of Texas graduate student, who was using a small robotic telescope at McDonald Observatory near Fort Davis, Tex., to troll for supernovas

Marvin approves... (0)

Anonymous Coward | more than 7 years ago | (#19037339)

"Now, THAT was an earth-shattering Ka-Boom!" - Marvin the Martian

That's no Supernova (3, Funny)

MHz-Man (1066086) | more than 7 years ago | (#19037527)

It was a precursor bomb! Looks like someone's copying the Shofixti's tactics.

Re:That's no Supernova (0)

Anonymous Coward | more than 7 years ago | (#19039883)

You sir, made my day. Star Control 2 was such an awesome game.

heavy elements (1)

mapkinase (958129) | more than 7 years ago | (#19037721)

Does anybody know any resource that lists how most likely all the elements originated from stable baryons and electrons, including chains like element1->element2+element3 (fusion) -> element4 (fission) -> element5,element6 with estimates of conditions necessary for each transition to happen?

Re:heavy elements (2, Informative)

stewardwildcat (1009811) | more than 7 years ago | (#19038317)

http://en.wikipedia.org/wiki/Nucleosynthesis [wikipedia.org] its called nucleosynthesis. The reaction chains that fuse in the sun are called nuclear reaction networks. There is a lot of information available on this but Wikipedia gives a nice overview./

Re:heavy elements (2, Informative)

navyjeff (900138) | more than 7 years ago | (#19038329)

I would start with a chart of nuclides [bnl.gov] and a chart of the current model of subatomic particles [particleadventure.org] to investigate the chain of fusions and fission.

I hope you like physics, though. The chart of nuclides can be a bit confusing at first.

Re:heavy elements (1)

mapkinase (958129) | more than 7 years ago | (#19040617)

This is quite useful especially the chart, but not as an answer to my question. Where are the links between elements?

Black hole creation (1)

tygt (792974) | more than 7 years ago | (#19038695)

The SN 2006gy data suggest that spectacular supernovas from the first stars - rather than completely collapsing to a black hole as theorized - may be more common than previously believed.
From my memory (most likely faulty - I'm sure of getting correction from this group ;)) of supernovae processes, I seem to recall that when there's a sudden energy output drop (typically due to running out of one fusion fuel, such as C/N/O in a red giant), stellar collapse begins; this collapse may be halted by increased pressures and temperatures "igniting" the next fuel in the stellar chain (H->He, He->C/N/O).

With massive stars (though not as massive as TFA discusses) the final collapse causes a shockwave that finally ignites a layer deep in the star which burns so hot and explosively that it blows the outside layers of the star off, giving us the nebula.

The leftover, however, continues with its collapse, as there's no long enough star left to run much fusion - especially of the heavier "ash" at the core, which may even be elements up to iron, which takes more energy to fuse than the fusion gives out in return, and thus is a "heat sink".

My question, based on this (admittedly faulty) memory, is two-fold:

  1. Does this 100-200 solar mass star completely explode, or is there a remnant left behind?
  2. If there is a remnant, how big (massive) is it, and should we expect to find a neutron star or a black hole there?

Google Reader clips the title (1)

kestasjk (933987) | more than 7 years ago | (#19038769)

To "Powerful Supernova May Be Related To Death", which I thought was a bit weird.

eddington limit, 120 solar masses Max (1)

Anonymous Coward | more than 7 years ago | (#19039045)

Should about 120 solar masses be maximal limit for a star size, because that is approximately the Eddington limit.

Eta Carinae (2)

phrostie (121428) | more than 7 years ago | (#19039615)

in the space.com article on this they mention that our own MilkyWay has a star about to go SuperMasive Nova at any time called Eta Carinae. Eta Carinae is about 7000 light years away so they say we are safe, but the Nova from last September eventually became brighter than it's own galaxy. So what i )BÇm wondering is even if we are safe from debris from this soon-to-be nova, what about an EMP from it?

200 solar mass possible? (2)

Dasher42 (514179) | more than 7 years ago | (#19040081)

Do we know that 200 solar mass stars can exist within the Eddington limit [wikipedia.org] ? To summarize, higher mass will increase the energy output of the star's fusion reactions, and there's a point where this can more than counter the force of gravity. How would a star exceed this? Are collisions or mass accretion from another object likely?

Old News... (3, Funny)

rthille (8526) | more than 7 years ago | (#19040579)


Slashdot, 240 million years behind the times.

(I should probably post this anonymously :-)
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