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Astronomers Successfully Predict Appearance of Supernova

Posted by timothy on from the lucky-guess dept.

schwit1 writes: For the first time ever astronomers have been able to predict and photograph the appearance of a supernova, its light focused by the gravitational lensing caused by a galaxy and the dark matter that surrounds it: "The NASA/ESA Hubble Space Telescope has captured the image of the first-ever predicted supernova explosion. The reappearance of the Refsdal supernova was calculated from different models of the galaxy cluster whose immense gravity is warping the supernova's light." What makes this significant is that the prediction models were based on the theory of gravitational lensing and required the presence of dark matter to work. That they worked and were successful in predicting the appearance of this gravitationally bent light (bent by the dark matter it passed through) is a very strong confirmation of both concepts.

12 of 86 comments (clear)

  1. Prediction of What? by tinkerton · · Score: 4, Informative

    They didn't predict that a supernova was about to happen. They'd already seen the supernova happening in its ghost image created by gravitational lensing. They predicted where another image of the supernova would turn up.

    1. Re:Prediction of What? by pjt33 · · Score: 4, Insightful

      "the first-ever predicted supernova explosion" certainly sounds that way. The subsequent mention of reappearance mainly serves to confuse.

  2. Re-Watching a Supernova by Henning+Rogge · · Score: 5, Interesting

    It is a quite interesting thing being able to "re-watch" a Supernova from the beginning because the light has multiple paths towards Earth so we got a "warning" when it will happen.

    The problem with a lot of Supernova explosions is that we often don't know what happened in the early phase (until it became bright enough to be noticed in wide-field pictures). It is most likely "a little bit" too far away to learn what type of star has exploded, but it still a great opportunity.

    1. Re:Re-Watching a Supernova by KGIII · · Score: 2, Interesting

      I'm just waiting for someone to pipe up that DM doesn't exist while not actually knowing what DM is. There are a few people who have valid opinions on it but almost all of the ones that I've noticed don't actually know what it is. (It's not really anything too specific yet, but we've got some ideas and some math. It's a placeholder.)

      --
      "So long and thanks for all the fish."
    2. Re:Re-Watching a Supernova by KGIII · · Score: 2

      Sort of true. I mean, yeah, it could turn out to be an effect caused by purple unicorn farts and it would still be dark matter.That's unlikely, and all, but it could happen. Something is causing this effect. Of course, some people seem inclined to not know the difference between dark energy and dark matter but that's a topic for another day.

      I am not a physicist. I am a mathematician. I do find it fascinating but it's just a hobby.

      --
      "So long and thanks for all the fish."
    3. Re:Re-Watching a Supernova by KGIII · · Score: 2

      We don't really know. The naming is unfortunate. It makes people come to all sorts of conflated confused conclusions - often without any help from others. ;-) I liken it to calling it the God Particle. A very unfortunate naming process.

      What DM is, and I'm just a layman, is what ever it is that causes this effect. Now, we've got some ideas and some maths and some of it even works. Proving this seems to be a bit of a stretch at this point but there are some folks thinking we might be able to really test it a bit more and draw some conclusions. We seem to be able to detect something, something new, and that something is where the effect, gravitational lensing, is coming from.

      Given that they were able to make this prediction and then have it come true means we're getting a bit closer to at least detecting concentrations of DM if not actually finding out what it really is. The Chinese just sent up a satellite the other day. That may get us somewhere closer. This isn't going to be quick or easy and we're going to go through a lot of theories before we're able to come up with a consensus. The word "we" is "we as in humans." I am not a physicist. I am a maths geek and I find the subject fascinating. I do find QM a bit confusing. :/

      --
      "So long and thanks for all the fish."
  3. Dark Matter testable predictions by Anonymous Coward · · Score: 4, Insightful

    ESA Hubble Space Telescope has captured the image of the first-ever predicted supernova explosion. ... What makes this significant is that the prediction models were based on the theory of gravitational lensing and required the presence of dark matter to work.

    The important part here seems like confirmation of testable predictions made by Dark Matter theories. That's how science works: you have to make a falsifiable theory that makes testable predictions. Those predictions are then tested, to lend evidence toward or against the theories. This is key evidence in favor of Dark Matter.

    1. Re: Dark Matter testable predictions by Anonymous Coward · · Score: 3, Informative

      That it obeys the rules that dark matter would have to obey, and disobeys every theorem of mond that has ever been proposed.

      Duh.

      What else did you think a test and validation of a theory would incur? Cookies and presents for all?

    2. Re: Dark Matter testable predictions by HiThere · · Score: 2

      It may well tell us details about the distribution and clumpiness of dark matter. That could be quite significant.

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
  4. Re:Dark matter or MOND? by Khashishi · · Score: 3, Insightful

    MOND is largely discredited by the bullet cluster measurements.

  5. Neutrinos showing supernova by Etherwalk · · Score: 2

    It is a quite interesting thing being able to "re-watch" a Supernova from the beginning because the light has multiple paths towards Earth so we got a "warning" when it will happen.

    I though we were able to notice supernovas a short time in advance of when they occurred visually because neutrinos from the explosion make it out of the star well in advance of the other stuff. (So we see a few neutrinos and can tell the supernova is about to be visible).

    Can someone confirm or deny? It's been a long time since I took astrophysics.

    1. Re:Neutrinos showing supernova by Anonymous Coward · · Score: 2, Informative

      We can ... in theory. The trouble is that our neutrino detectors aren't as sensitive as our optical telescopes. We can detect optical supernovae billions of light-years away, but we can only detect the neutrinos from a supernova within a few hundred thousand light-years.

      The most recent supernova that was close enough to detect in neutrinos was in 1987 (SN1987A). Three detectors spotted neutrinos from it a few hours before the optical supernova, but they only noticed this coincidence after the fact.

      We're a bit more savvy about it now, and I bet that, if there was another nearby supernova setting off multiple neutrino detectors, they'd notice the coincidence and send out an alert within a few minutes. They just need another nearby supernova (roughly, within our own galaxy), which happens once a decade or so.