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Picture of galaxy

  1. Mar 19, 2010 #1
    How was we able to take the pictures of galaxies?
  2. jcsd
  3. Mar 19, 2010 #2
    The Hubble?
  4. Mar 19, 2010 #3
    You can see galaxies with telescopes on Earth, what do you mean?
  5. Mar 19, 2010 #4
    You can even see adromeda with the naked eye, you should google the question you asked before putting it on this site
  6. Mar 19, 2010 #5
    Kinda, I mean, with all that atmosphere and whatnot it's definitely harder. The good pictures of stuff far away probably come from satellites.
  7. Mar 19, 2010 #6


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    Wrong. There are plenty of land-based telescopes that image distant galaxies quite precisely. While it is true that space-based telescopes don't suffer from atmospheric extinction and can gather light of wavelengths that are absorbed by the atmosphere, they are necessarily MUCH smaller than the 'scopes that we can operate on Earth, and their targeting requirements, approved observation-time, etc restrict how much stuff we can image. In contrast, Earth-based telescopes can be used for dedicated survey work. Schmidt telescopes have done all-sky surveys in the Northern and Southern hemispheres for for decades.
    Last edited: Mar 19, 2010
  8. Mar 19, 2010 #7
    Can't argue with the truth.

    But I guess you CAN'T get the REALLY far away stuff because it's too red-shifted :P
    (Does the smallness of the telescope hurt it's ability to resolve the red-shifted wavelengths well?)

    Does the same phenomenon that causes 'twinkling' stars effect land based telescopes at all?
  9. Mar 19, 2010 #8


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    Well, we should be able to dig deeper with the upcoming Webb telescope. It will feature much deeper IR penetration than Hubble. Still, ground-based telescopes will do much of the heavy lifting. We can't launch something equivalent to Keck, LBT, etc, so the eyes on the ground will have the major role. Orbiting instruments have some obvious advantages, but aperture and angular resolution are the domain of ground-based instruments. Adaptive optics are helping operators of ground-based 'scopes get crisper images, and that technology is still improving.

    And no, space-based telescopes don't have problems with "twinkling", because that is an effect of atmospheric refraction.
  10. Mar 21, 2010 #9
    An advantage of ground based telescopes: adding, upgrading, or just fiddling with optics, filters, instruments, etc. No need for a space walk or launching another 'scope.

    The far away stuff is just too dim to image without days of exposure. The Hubble Ultra Deep Fields http://en.wikipedia.org/wiki/Hubble_Ultra_Deep_Field required over eleven days of imaging.

    It would be nice to have a few 1000 meter diameter telescopes in space.
  11. Mar 21, 2010 #10


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    Obviously it is not our galaxy. Pictures of other galaxies are old news.
    Last edited: Mar 21, 2010
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