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Supernova Discovered

Posted by timothy on from the amateur-hour's-brightest-stars dept.

hey! writes: "A supernova was found last Wednesday in the M74 galaxy (announcment can be found here :http://www.aavso.org/newsflash/nf904.shtml. It is not visible to the naked eye, but was discovered with at 10 inch telescope and is getting brighter -- it may be visible in amateur instruments as small as 4", according to Lew Gramer of the IAAC list. More information is available at seds.org including a very nice before and after picture."

10 of 34 comments (clear)

  1. Re:When did it happen? by Chris+Brewer · · Score: 3, Informative

    Try thousands, if not millions of years ago.

    Our nearest celestial neighbour is Alpha Centauri which is 4.5 light years away. This means if it went supernova, we wouldn't know about it for 4.5 years.

    --
    Consultancy: If you're not part of the solution, there's money to be made in prolonging the problem
  2. Re:When did it happen? by vtaluskie · · Score: 3, Informative
    FYI this link lists the distance as 30-40 million light years.... so my vote would be for the it happened millions of years ago :)

    Additional linkage from APOD

  3. Re:When did it happen? by cybrpnk · · Score: 5, Informative

    M74 is 30 million light years away so this supernova went off 30 million years ago. This is about 15 times farther away than the Andromeda galaxy, which is the closest "true" galaxy to the Milky Way.

    No criticism intended, but if you are wondering if something visible in a distant galaxy occurred days, weeks or months ago, you need to get a fast update on just how BIG the universe is. I recommend a quick trip to the Powers of Ten website....

  4. Re:The galaxy went dim? by cronio · · Score: 2, Informative

    I would imagine it's just because it was taken with a different telescope, and/or with different settings. The galaxy next to it is smaller and in a different place, too.

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  5. Might be hypernova by eclectro · · Score: 5, Informative

    This promises to be one of the brightest supernova in a long time. I hope they point the hubble torwards it.

    There is an excellent site that will track the progress of this supernova here

    Space.com has an article about hypernova here. More detail about hypernova mechanics are here and here

    If they can catch a Gamma-Ray Burst with this object, then this will be a pretty big deal.

    --
    Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
    1. Re:Might be hypernova by DustMagnet · · Score: 2, Informative

      By following the above link to rochesterastronomy.org, I was surprise to learn that this slashdot story isn't even news.
      Acording to this site:

      For the year 2002, 43 supernovae have been reported (282 last year).

      So one more isn't much to write home about (or slashdot).

      --
      'SBEMAIL!' is better than a goat!!
    2. Re:Might be hypernova by frunk · · Score: 2, Informative

      Actually there are two elements that make this interesting. One is the fact that they caught it so early, when the supernova was still brightening. This is relatively rare. Second, this is the nearest supernova that they've found before the gamma ray burst has occurred.

      Of course, as has been pointed out, it's also significantly brighter then most supernovas.

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  6. Re:The galaxy went dim? by eclectro · · Score: 2, Informative

    The size of the telescope, the lenses used in the objective, atmospheric conditions, the different filters used, the CCD cameras used, the length of the exposure time, all play a huge factor in how the picture looks.

    Because there are so many different variables involved, it's common to see variations like this. The galaxies do not "go dim".

    More on M74 here.

    --
    Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
  7. Re:The galaxy went dim? by SIGFPE · · Score: 4, Informative
    You're in for a surprise. Many of the pictures in the world around you are processed significantly - whether it's for advertising purposes or in a scientific journal. You can tell very little about how bright something is by looking at a photograph. In order to bring an astronomical picture to the public it goes through many operations. Typical processes include:
    1. False colour. A photograph may in fact be in the infrared or ultraviolet spectrum in which case these wavelengths are replaced by visible light so that we can see them.
    2. Compositing. Often astronomical pictures are formed by compositing together different images - for example images taken with different coloured filters or even completely different sensors.
    3. Filtering. For example the raw output from a CCD might be sharpened using a suitable digital filter (which can introduce other artifacts such as 'ringing').
    4. Normalisation. The overall brightness of the image may be adjusted so that important features are neither too bright or too dark.
    5. Cleanup. An image might be cleaned up to remove effects like lens flare or even dirt on the sensor.
    6. Artistic modifications. If an image is on display to the general public it might be modified in a package like photoshop to give the best looking press release.
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    -- SIGFPE
  8. Re:In M74? by Doctor+Fishboy · · Score: 2, Informative

    These supernova follow a reasonably well-known light curve, and so by measuring its apparent brightness and knowing what its actual brightness is, you can get a rough cut at the distance.

    If it was in our galaxy, it would be MUCH brighter.