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Phases of the moon

  1. Aug 5, 2006 #1

    Just a stupid doubt...when the moon is in FIRST QUARTER or LAST QUARTER, their angular separation is of 90 degrees; question: is it the TRUE angular separation or is it the difference of ecliptic longitudes?

    Kind regards,

  2. jcsd
  3. Aug 5, 2006 #2


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    First and last quarter moons result from the earth-moon line being 90 deg. from the earth-sun line.
  4. Aug 5, 2006 #3
    That was my initial guess :)


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