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Questions about geometric albedo and phase angle

  1. Mar 17, 2012 #1


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    If our sun is the source of illumination, how can an object be observed from the Earth at full phase? Wouldn't the Earth eclipse the object? So then why can we see a full moon during full phase? Is it because the moon's orbit is inclined wrt to the Earth-Sun orbit? If so then wouldn't this by definition not be full phase?
  2. jcsd
  3. Mar 17, 2012 #2
    You're right, full phase isn't perfectly-completely illuminated... but the deviation is small. Full phase is defined relative to the lunar cycle, i.e. full = maximum, not complete illumination. Eclipses do happen when the earth blocks the sunlight from the moon---which is when it would have been a truly complete full-moon.
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