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Supernova Birth Observed From Orbiting Telescope

Posted by timothy on Wed May 21, 2008 03:42 PM
from the you-should-see-the-superplacenta dept.
FiReaNGeL writes "Astronomers have seen the aftermath of spectacular stellar explosions known as supernovae before, but no one had witnessed a star dying in real time — until now. While looking at another object in the spiral galaxy NGC 2770, using NASA's orbiting Swift telescope, scientists detected an extremely luminous blast of X-rays released by a supernova explosion. They alerted 8 other telescopes to turn their eyes on this first-of-its-kind event. 'We were looking at another, older supernova in the galaxy, when the one now known as SN 2008D went off. We would have missed it if it weren't for Swift's real-time capabilities, wide field of view, and numerous instruments.'" Bad Astronomy has an excellent, well-illustrated story about the discovery as well. I Don't Believe in Imaginary Property contributes a link to the BBC's coverage, and adds a nugget gleaned from Ars Technica: "SN 2007uy's collapse caused an X-ray burst of about 10^39 joules, most likely due to the 'shock break out' when the energy of the core's collapse finally reached the neutron star's surface."
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[+] Youngest Galactic Supernova Found, But No Aliens 184 comments
Simon Howes writes "After searching for decades, astronomers have found a supernova in our galaxy! So it wasn't little green men we were waiting for. It's located very near the center of the galaxy, about 28,000 light years away, and it's only at most about 140 years old. Quote from Bad Astronomy: 'If you're wondering what all the buzz has been about the past few days over a NASA discovery, then wait no longer. No, it's not aliens or an incoming asteroid. Instead, it's still very cool: astronomers have found the youngest supernova in the Milky Way.'" FiReaNGeL contributes a link to coverage on e! Science News; I think Wired's account of the super-hyped tele-press-conference is the funniest.
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  • "SN 2007uy's collapse caused an X-ray burst of about 10^39 joules
    But how many gigawatts is that?
    • 2.77777778x10^26 gigawatt-hours.
      • by Lord Crc (151920) on Wednesday May 21 2008, @04:44PM (#23498004)
        I just had to try to put that into perspective, so I looked up [doe.gov] the net annual usage of electricity in the US. If we had somehow captured, converted and stored all that energy, the US would spend about 45 million years using it up (assuming linear growth similar to the last 10 years, and I didn't screwed up the math).
        • Doesn't seem like much at all. Put it this way, just about anything that has ever happened on Earth has been powered by the Sun. Only a tiny fraction of the Sun's output lands on Earth and yet the Earth has been powered for more than a couple of billion years. Yet you're saying that the final death throes of a star in which it's doing the most intense thing that every happen in its lifetime that it throws of enough energy to feed a single 21st century nation for a few million years. Paltry!
          • This doesnt seem to be that much because he alse assumes linear growth of energy consumption over all those millions of years.

            At the end of those 55 million years, ever person in the US would use as much energy as a small country...
        • by rssrss (686344) on Wednesday May 21 2008, @07:03PM (#23499110)
          Uh? According to the annual report at the web site you linked, the total energy usage of the US (not including isolation) is about 100 Quads per year. A quad is 10^15 BTUs. One BTU is about 1055 Joules. So, the US uses ~10^20 Joules per year (J/a). The whole world uses about 4 or 5 times that amount. But, lets say the whole world uses 10^21 J/a. At that rate it will take 10^18 years to use 10^39 J. I don't think that the universe will last a substantial fraction of that time period.
          • 45 million years struck me as a little too soon for the U.S. to go supernova, but after watching the U.S. for just the past few years, I think maybe we could pull off a regular nova or at least a stellar flare.
          • I should have specified that I based it on electricity use. You make a good point though.
          • The universe as we know it might actually live that long and much longer, since the proton half-life (assuming that the Grand Unification Theory is correct and protons do decay after all) is currently estimated to be at least 10^35 years.
  • by woodchip (611770) on Wednesday May 21 2008, @03:51PM (#23497464)
    Now, Who put metal in the microwave?
  • by Salsaman (141471) on Wednesday May 21 2008, @04:07PM (#23497640) Homepage
    I felt a great disturbance in the Force, as if millions of voices suddenly cried out in terror and were suddenly silenced. I thought it was the beans I had eaten the night before.
  • This may seem like a silly question, but were the astronomers able to capture data of the entire event, starting before the initial burst of energy was observed?

    Were they already recording data when the new supernova became apparent, is there some sort of "astronomical TiVo that continuously records data in the hopes of inadvertently observing an event such as this one, or did the scientists need to press 'record' once they observed the initial burst of energy?

    I only ask, because the article's comparision t
    • Re: (Score:3, Informative)

      The astronomer was looking at another supernova very close to the one in question - the number i read was 8 seconds after the start (of X-ray emissions) of the new supernova - they started getting data. Indeed they got really lucky here.
      On a completely unrelated note
      Have you ever seen a supernova blow up?
      No, but if its anything like my old chevy nova it will light up the night sky
  • How long ago?
  • by Doc Ruby (173196) on Wednesday May 21 2008, @04:30PM (#23497856) Homepage Journal
    This supernova event's description includes a mention of how stars make only the elements no heavier than iron:

    After a few million years of generating energy by fusing light elements into heavier ones (hydrogen to helium, helium to carbon, and so on), the core runs out of fuel. Iron builds up in the very center of the star, and no star in the Universe has what it takes to fuse iron.


    Heavier elements (like uranium [wikipedia.org]) are actually created in the supernova event itself:

    Along with all elements having atomic weights higher than that of iron, it is only naturally formed in supernova explosions.


    So this observation is actually recording the actual origin of all the elements heavier than iron. All the jewelry and aerospace materials you've ever seen, all the copper you use in wiring and plumbing, all elements [wikipedia.org] with atomic numbers from 27 (cobalt) through 94 (plutonium) were made in crucibles like the one we just took home movies of.
    • by jmichaelg (148257) on Wednesday May 21 2008, @05:18PM (#23498250)
      ...all elements with atomic numbers from 27 (cobalt) through 94 (plutonium) were made in crucibles like the one we just took home movies of.

      Nucleo-genesis doesn't stop at plutonium. The transuranic elements get created just as well. The only difference between them and the elements up to and including plutonium is longevity. I'll bet a lot of astronomers were vying for scope access so they could look for elements in the island of stability. [wikipedia.org]
  • by Anonymous Coward on Wednesday May 21 2008, @04:43PM (#23497976)
    I would like to correct this part of my submission:

    SN 2007uy's collapse caused an X-ray burst of about 10^39 joules, most likely due to the 'shock break out' when the energy of the core's collapse finally reached the neutron star's surface."


    That should've been SN 2008D, not SN 2007uy. I confused the old supernova with the new one somehow, which is pretty bad considering it even has the year as part of the name. The NEW supernova is the one whose X-ray burst released approximately 10^39 joules.

    Also, the unnamed "scientists" who were lucky enough to find this are Alicia Soderberg of Princeton University & her colleagues, just so we give credit where credit is due.

    - I Don't Believe in Imaginary Property [eff.org]
  • by commodoresloat (172735) * on Wednesday May 21 2008, @04:55PM (#23498084) Homepage
    Supernovas all look the same at birth but it's proper form to smile politely and congratulate the parents anyway.
  • by DrJay (102053) on Wednesday May 21 2008, @05:06PM (#23498166) Homepage
    Whoever wrote the summary of the story on Ars had a bad day. The figure in Joules is right, but it came when the energy hit the surface of the existing star, not whatever remnant remains of the core.

  • Ars Technica: "SN 2007uy's collapse caused an X-ray burst of about 10^39 joules, most likely due to the 'shock break out' when the energy of the core's collapse finally reached the neutron star's surface."

    I think they mean SN 2008D, the new supernova that was just detected by its X-ray flash. SN 2007uy was the old (31 Dec 2007) supernova they were observing at the time that SN 2008D went off.
  • automation (Score:4, Interesting)

    by Anonymous Cowpat (788193) on Wednesday May 21 2008, @06:56PM (#23499058) Journal
    So is there some sort of automated system which gets every major telescope on, or orbiting, the planet to drop what it's doing and point at supernovae (if they can see them) as they appear? Or does someone have to get a telephone directory out and start asking some unfortunate Chilean the way to the beach in a loud voice?

    I understand that astronomers have been wanting to gather as much data as they can from as many telescopes as they can on supernovae as they appear, and have organised lots of telescopes en masse before, I just wonder by what means it's achieved.

    I also think that it would be incredibly cool if, in the dusty control room of an observatory up a mountain in Hawaii or somewhere, there was a big red button labeled "push in case of supernova", which grabbed the co-ordinates currently being observed, and took over every other telescope on the planet to point at them.

    Also, have they done interferometry with this data? because that would be an awesomely large telescope diameter (and awesomely small resolution angle).
  • by flabbergasted (518911) on Wednesday May 21 2008, @09:10PM (#23500042)
    Were any neutrino telescopes collecting data at the time? If so, did they see a signal? The delay between the time of arrival of the X-ray burst and the neutrino signal would put bounds on the mass of the neutrino. Given the distance to the supernova, there probably wasn't much of a signal, but it would be interesting to know if anything was seen.
    • Re: (Score:3, Informative)

      The delay between the time of arrival of the X-ray burst and the neutrino signal would put bounds on the mass of the neutrino.

      Actually, the neutrino burst would arrive before the X-ray burst. The neutrinos are released as the degenerate gas at the stellar core collapses to neutronium; they pass through the surrounding material as if it wasn't even there, and set out into the universe immediately.

      Once the neutron core has formed, further infalling matter hits the hardest surface in the universe, and this

      • But as the detectors are running 24/7, there might be a spike.
        OTOH, this isnt andromeda, so not sure about what countrates to expect. Not a lot, after a small rule-of-thumb calculation, even in the best detectors...
    • Re: (Score:2, Insightful)

      time is relative. if you see it now, it's real time. Too bad is not naked eye close.
    • "That means they watched in 'real time' something that happened about 100 million years ago?"

      Thanks, HughesNet!
    • Yes, it happened ~100 million years ago and from our point of view we just watched it in real time.

      And the sun in the sky is 8 minutes old.

      And your conscious mind is 1/2 second behind.

      And I'd really rather you not remind me of disturbing things like this and leave me in peace with my bottle of Cragganmore. Now go away.
    • by SBacks (1286786) on Wednesday May 21 2008, @04:03PM (#23497592)
      Yes, space is big and light takes a long time to get to us. By 'real time', they mean they are watching the photons coming from the actual death of the star, and not the photons coming from the debris from years and years later.
    • by thermian (1267986) on Wednesday May 21 2008, @04:06PM (#23497628)
      Since nothing that is observed is happening at the time of the observation, real time is as good a term as any.
      • Since nothing that is observed is happening at the time of the observation, real time is as good a term as any.

        Ooh, that was good, and just about closes the book on the whole argument.
        In fact, now that you mention it that way, a lot of things are starting to make more sense.
        Words to live by.
      • Since nothing that is observed is happening at the time of the observation, real time is as good a term as any.

        I'd say that since according to Relativity we're observing this event at the earliest point in time it would be physically possible for us to observe it, "real time" is a great term.
    • By your definition, nothing you see is real time.
      • <pedantic>

        Exactly.

        Even if I hold a flashlight right next to my eyeball (ouch!) and turn it on, there is still a small -- albeit infinitesimally small -- delay between the point when the photons exit the flashlight and when they impact my retina. Thus, I am not watching the flashlight turn on in "real time", although for all practical purposes, it is close enough.

        </pedantic>
      • nothing you see is real time.

        D'uh!
    • Old news (Score:5, Funny)

      by commodoresloat (172735) * on Wednesday May 21 2008, @04:54PM (#23498072) Homepage
      Yeah that's right, another dupe from slashdot; this story was covered 97 million years ago when it actually happened.
    • The fact that we can't tell with absolute precision how long the light has been traveling is a good example of why we use the term real time. In our frame of reference, it is happening in real time.
    • That means they watched in 'real time' something that happened about 100 million years ago?

      Yeah, exactly. Wake me up when a supernova explodes down the street.

      Actually there are inertial frames in which this supernova practically just exploded, e.g. that of the neutrinos which just arrived here from the supernova traveling at almost the speed of light. They would see their flight path undergo Lorentz contraction; as the velocity approaches c the distance shrinks to zero.