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Brightness of objects through a telescope

  1. Feb 11, 2016 #1
    Hi my question is about how the brightness of stellar objects is effected when we look at them through a telescope.
    Firstly when I looked through a telescope I noticed there were more stars I could see. Is the reason because a telescope can gather more light than our eye or does it have something to do with magnification.
    Also the more we magnify, an object such as the moon appears dimmer. And if we look at objects on Earth they seem to not change brightness much, maybe they become brighter I'm not sure, but I'm wondering why.
    Lastly I would like to extend this question to groups of stars like in nebuae. Do they appear btighter or dimmer through telescopes?
    I'd like to conducted an investigation of how brightness is effected by magnification and I'm just not sure I'd get any results, I'm also stugling to find a good way yo conduct it, I'm thinking of observing a bulb in a dark toom through different lenses, I haven't thought if s discreet way of obtaining measurements yet. Any suggestions? Or perhaps an alternative like counting the number of stars I can see through a telescope by changing the eye peices?
    Thanks in advance :D
  2. jcsd
  3. Feb 11, 2016 #2


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    The light gathering power of a telescope obviously makes stars appear brighter. Magnification only improves the ability to discern individual stars. Since all stars are so distant they appear to be point sources of light, magnification does not dilute their luminosity like it does for planets.
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