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Interesting thought about black holes

  1. Aug 10, 2010 #1
    Well since we will never see something go into a black hole, wont we see everything the black hole tries to swallow around it? So wouldn't it be possible to see a black hole since a bunch of things would be around the event horizon.

    Answers are appreciated.
  2. jcsd
  3. Aug 10, 2010 #2
    Thats pretty much how astronomers spot blackholes. The gasses that are being swallowed by the hole emmit X-ray radiation which is mainly what they look when searching for black holes.
  4. Aug 10, 2010 #3


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    Yes, but this doesn't have anything to do with time dilation. This is simply normal matter accreting onto the black hole. By the time things start redshifting and slowing down near the event horizon, it's likely that these signals would no longer be observable.
  5. Aug 10, 2010 #4
    I was pretty sure they haven't spotted black holes from the show I saw on tv..
  6. Aug 10, 2010 #5
  7. Aug 10, 2010 #6


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    Direct detection of black holes is, by definition, basically impossible. Detection of accretion discs radiationg unbelievable amounts of high energy radiation is more than possible [e.g., quasars] Black holes can also be detected by gravitational effects in binary systems and lensing. While not direct detection, the evidence is fairly compelling.
  8. Aug 11, 2010 #7
    Hmm tv shows like to trick me I guess :p
  9. Aug 12, 2010 #8

    George Jones

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    There is a good chance that, within a decade or so, we should be able to "image" in this way the astrophysical black hole at the centre of our galaxy. See


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