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The moon

  1. Apr 14, 2006 #1


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    Did anyone in the uk see the moon last night ? it was so bright, and seemed
    to have a three lobed halo surrounding it, is this just atmospherics ?
  2. jcsd
  3. Apr 14, 2006 #2
    I'm not from the UK, but I watched the moon occult Spica last night.
  4. Apr 14, 2006 #3
    Its an intresting question because it sometimes happens to look larger or brighter but the only thing coming in my brain is the atmosphere's gases causing the light to get some diffrences but I'm not sure and I'll be waiting eagerly for an answer....:)
  5. Apr 14, 2006 #4


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    It was very spectacular. I saw it as it just popped over the horizon where it was a deep orang colour and it gradully got brighter as it rose higher above the horizon. The fact it appears larger is due to it rising on the horizon with houses and other points of reference etc. when the moon is high in the sky and has no points of reference (other than stars) it appears smaller. This is all an optical illusion such as the two bars of the same length between the tapering rails. The one at the widest point of the rails appears to be longer even when you know it isn't.

    The moon can appear bigger in the sky though. As we all know it has an elliptical orbit and when its at its closest point it has its greatest angular size and at its furthest point it has the smallest angular size.

    I wish I'd taken some pictures of it because as you say the moon was so bright it cut through the haze perfectly but left this amazing halo.
  6. Apr 14, 2006 #5
    Unfortunately, as great as the Moon is to watch, most astronomers call that light pollution. I saw a Moon halo myself the other night, similar to a Sun halo.

  7. Apr 14, 2006 #6


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    brightness due to it being a near-full moon (and perhaps atmospheric clarity?)

    halo effects due to the earth's atmosphere

    But a tolerable kind. Deep-sky observing is best done at moonless times (so the glare of the moon does not wash out the dimmer objects). But exploring the moon can be great fun to an astronomer too (easy, clear, lots of interesting features & details).
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