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Space Science

Brightest Supernova Discovered 63

Maggie McKee writes "Astronomers have spotted the brightest supernova ever seen — it is intrinsically two to three times brighter than any previously recorded. It has many characteristics of a type Ia explosion, but has hydrogen in its spectrum, unlike other type Ia's. That suggests that this supernova resulted from the collision of two stars — most likely a white dwarf and a red giant — rather than from an exploding white dwarf. If so, it might affect the interpretation of previous cosmological studies that depend on type Ia 'standard candle' observations, like dark energy. But other astronomers say merger-triggered explosions are probably rare and therefore won't throw a wrench in the works."
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Brightest Supernova Discovered

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  • Book (Score:3, Informative)

    by 2.7182 ( 819680 ) on Thursday January 04, 2007 @01:08PM (#17460038)
    If you are really interested in the topic I recommend

    Fraser, Craig G.
    Title The cosmos : a historical perspective
    Westport, Conn. : Greenwood Press, 2006.

    I learned a lot from it about novas.
  • Maybe this one will draw in a bigger crowd than Lukas Rossi.

    (I kid, I kid! He's an upstanding Canadian guy ...)
  • Do not look into the supernova with your remaining eye!

    (theres a lot of bright shiney things around at the moment, I'm surprised anyone can see anything at all)
  • If, hypothetically, you found yourself to have evolved first or to exist in an otherwise empty galaxy - then you might look for an easy way to get the attention of any civilizations in any other galaxies. If you could move a star (details, details) then this would be a good way to get yourself noticed.

    Of course, you would want to do it several times over a short period, and you would want it to coincide with a radio transmission that actually contained some data. So the way it works is, a hundred million
    • by Anonymous Coward
      someone write it up
    • "If, hypothetically, you found yourself to have evolved first or to exist in an otherwise empty galaxy - then you might look for an easy way to get the attention of any civilizations in any other galaxies."

      Like the Borg?

      Greg Bear hypothesized in Darwin's Radio that it might be unwise to announce your presence before you are able to defend yourself. Think of a baby bird in a nest, chirping loudly when it's mother is not around.

      Of course, in your scenario, the civilization has the power to move stars, and to
      • The thing is, when do you know that a civilization is "capable of defending itself"? You can never answer that without first knowing the capabilities of other surrounding civilizations. I mean, right now we got nukes and jet fighters. For all we know our stuff might be the shiz-nit to beat in the universe, or they could be absolute junk compared to any other civilization in existence. In 100 years when we have Mk VII Vipers flying around . . . the same could still be true. They could be state of the ar
        • It's a little simpler than that.

          If some other civilization has the power to get here, and we don't have the power to get there, I'd say they have a technological advantage that would be overwhelming. If F16s are the most potent weapon in the universe, then I would say that we are not about to be visited any time soon, and thus we have nothing to worry about.

          But if you want to plan on the contingency of fighting an inter-galactic war, you should be technologically advanced enough to fight it - we can barely
          • Re: (Score:3, Interesting)

            by MBGMorden ( 803437 )
            You missed my point. The point is we can never, ever know how advanced our stuff is compared to theirs. We don't even know if there is a "there stuff". So yes if F-22's (not F-16's :D) are the most advanced thing we have nothing to worry about. But it don't matter if we got little intergalactic fighters with friggin laser beams attached to their friggin heads - if we haven't come into contact with another race yet then they could very well just swat them all like flies . . . . or they might come against
    • by east coast ( 590680 ) on Thursday January 04, 2007 @02:13PM (#17461410)
      If, hypothetically, you found yourself to have evolved first or to exist in an otherwise empty galaxy - then you might look for an easy way to get the attention of any civilizations in any other galaxies. If you could move a star (details, details) then this would be a good way to get yourself noticed.

      Just to poke a hypothetical hole in your hypothetical civilization...

      I think the real questions here is the evolution of technology by an alien culture. For what you've said to make sense this civilization would have to have the ability to guide stars in a significant fashion while not having the ability to do simple observance as we do today. IMHO that's just too far fetched.

      Consider our own little planet here: we have a limited ability to detect solar systems and radio signals from a distance within our own galaxy. Yet, we do not have the ability to jump to the next semi-habitable planet and stay there on a permanent basis. It's fairly clear that our ability to observe the cosmos is much much better than our ability to [work within/live within/manipulate] anything outside of our own little sphere of mud and rock.

      It's just a question of how a civilization could evolve in such a fashion as to be able to work with outer space but not be able to observe it beyond their own first-hand experience.

      If I had the insight or imagination to figure this out into a workable model I'd be one hell of a science fiction writer.
      • by oni ( 41625 )
        Consider our own little planet here:

        what I suggested is NOT for planet-to-planet communication. It's about "what do you do if you're alone in your galaxy." There are more galaxies in the universe than there are stars in any one galaxy. Just transmitting a radio signal (a-la contact) isn't going to get you noticed. Someone would have to point a arecebo-size telescope at your galaxy to hear your signal. That's very unlikely.

        So how do you get noticed? Cause a supernova. Or actually, a better idea would
        • > At any rate, the point is that you need a lot of energy to get civilizations
          > in other galaxies to notice you.

          Or a lot of directivity.

          Why would you bother, though? You won't get heard for millions of years.
          • by oni ( 41625 ) on Thursday January 04, 2007 @06:43PM (#17466150) Homepage
            Why would you bother, though? You won't get heard for millions of years.

            you don't do this because you expect to be heard. Remember, the universe that this happens in is one where life is so incredibly rare that you searched your entire galaxy and didn't find any (we're talking a class III civilization here). So, on the off chance that there is life in another galaxy you announce your existance.

            You'll never hear a reply - but if you don't do it, they will never hear YOU. On the other hand, if everyone follows my logic, then everyone will announce and you will hear from every civilization. And "hearing" from them probably means getting their version of the encyclopedia galactica. Everybody transmits everything they know.

            What more do you want, a conversation? If you transmit your entire body of knowledge and all your history and all your culture, what more is there to talk about anyway? What do you think, you're going to get on the live and go: "a/s/l????"

            Youre way of thinking, when you say, "why bother" is tragedy of the commons thinking. You don't want to take any action unless you personally get a return on that action. That's very selfish. If everyone else thinks unselfishly, then everyone will get everyone else's encyclopedia galactica.
        • My point has more to deal with what abilities an alien civilization may have and the returns of investment involved in pushing two stars together.

          Once you're at the point where you can influence the position of a star it's very unlikely that you're going to have a problem noticing other civilizations through pure observation, not being observed by others. I will grant you that waiting for someone to take notice of a weak signal across intergalactic space is such a terrible concept it's hardly worth conside
          • by oni ( 41625 )
            I see what you're saying, but here's the part I doubt:

            Once you're at the point where you can influence the position of a star it's very unlikely that you're going to have a problem noticing other civilizations through pure observation

            I wonder if the laws of physics allow seeing any kind of civilization in another galaxy. How big of a telescope do you need to hear normal radio communications in another galaxy (we're NOT talking about an intentional "hello world" signal. we're talking about TV and radar etc
            • Sometimes it's hard to wrap my brain around this, but that fuzzy glow is stars. We can't even see individual stars, just the fuzzy glow. How are we supposed to see radio on a planet around a star when we can't even resolve the individual star?

              And with our same limited technology you're proposing moving a star when we haven't even moved an asteroid yet? What's the debate here? If you're using our ability to see into another galaxy as proof of another civilizations ability to be able to observe their neighb
        • I think it was the astronomer Patrick Moore" [wikipedia.org] who recently described Gamma Ray bursts as "Alien industrial accidents".
    • by doi ( 584455 )
      So cool that Arthur C. Clarke already thought of it: http://www.prospect-magazine.co.uk/article_details .php?id=3828 [prospect-magazine.co.uk]
    • If you could move a star (details, details) then this would be a good way to get yourself noticed.
      True. I suspect this is another failed viral marketing attempt by Sony. Did any one happen to notice if the supernova was shaped like the letters P S P?
    • Sounds nice in theory, but i'd hate to think of the probabilities of a) a significantly advanced race able to do so b) a receiving race that is paying attention when the light and RF waves pass their planet, c) that they notice its non-random and d) the "data" sent in between is not mangled to death by the supernovae's shockwaves.

      I think a race able to move/detonate stars at will would try to think of a method that doesnt compound tiny probabilities so much =)

  • by Evets ( 629327 ) on Thursday January 04, 2007 @01:32PM (#17460552) Homepage Journal
    If it was so bright, how come nobody ever saw it before?
    • Re: (Score:3, Insightful)

      I don't know if you're being serious or not, but I'll answer anyway. Supernovae are transient objects: they show up suddenly and are very bright, growing to their maximum brightness within the first week. They then taper off and disappear in a few months. Astronomers will take a picture of a supernova every night and then graph its (apparent) birghtness as a function of time. This light curve is most useful if there's data from when the supernova is at its brightest, which is why it's best to catch supe
    • Why?

      Because it's not a supernova, but just one of the rappers in "Black Fangs", the famous Sagittarius group who lit up a nebular joint with cosmic weed or dark matter, after a concert to set off the after party!
  • FTA, it looks like the supernova is brighter than the host galaxy's core. Not a bad way to go out, if you're a star.
    • FTA, it looks like the supernova is brighter than the host galaxy's core. Not a bad way to go out, if you're a star.

      But quite a bad way to go if you're a budding civilisation in the aforementioned galaxy. Having your entire planet sterilised can really ruin your day.
  • How do they know? (Score:4, Insightful)

    by lazlo ( 15906 ) on Thursday January 04, 2007 @04:12PM (#17463678) Homepage
    OK, so this is calling into question one of the "standard candles" of astronomy and cosmology. But I'm curious exactly how? There's a fairly simple formula that relates absolute magnitude, relative magnitude, and distance. If you know any two, you can calculate the third. The whole concept of standard candles is that there are some events for which we know the absolute magnitude. This article is saying this is one of the standard candle events, but much brighter than ever before. The big question for me is, how do they know it's not just closer than ever before? My understanding is that the standard candle equations are the only way to determine distance at these ranges.
    • The article doesn't explain, so I can only speak generally (albeit professionally). It is possible that they have two of the three data points you mention; namely, apparent magnitude and a distance estimate for the parent galaxy. (There are a few ways to get good distance estimates without using the supernova as a standard candle; e.g., the galaxy is part of a cluster for which a reasonably good distance estimate exists.) From those they derive the unusual absolute magnitude. Which really shouldn't be a
    • The distance to the event can be estimated using its redshift; the redshift of the supernova itself, and/or the redshift of its host galaxy. For objects which are more distant than the Virgo Cluster (roughly), the redshift and Hubble's Law provide a very good _relative_ distance estimate. Using the redshift of this event, and the redshifts of other supernovae, we can see very clearly that this event is more luminous than the usual supernova, even if we don't have the _absolute_ distance.

      You _can_ argue th
      • by lazlo ( 15906 )
        That makes sense... I would say the alternative hypothesis would be that a solitary intergalactic binary star system went nova while traveling at a vector whose away-from-the-earth component approximated the redshift of the galaxy behind it. I can certainly see why that would be considered a bit of an unlikely event. I think the "colliding stars" theory is probably more likely.

    • Until they decide to have two good space based telescopes at opposite sides of their orbits, say 300million km wide. Or better yet. Earth orbit, and Jupiter orbit scope.
      • Until they decide to have two good space based telescopes at opposite sides of their orbits,

        Huh? Take a picture. Wait 180 days. Take a picture. Bingo. (err.. guess it won't work for supernova)
  • by StikyPad ( 445176 ) on Thursday January 04, 2007 @06:45PM (#17466184) Homepage
    Inversing the colors provides a more lifelike image. For the lazy. [imageshack.us]

One man's constant is another man's variable. -- A.J. Perlis

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