EnigmaticField
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We are experiencing a regular series of the Aldebaran occultations by the moon now. I read this in the article http://www.skyandtelescope.com/observing/moon-covers-bright-star-aldebaran/. What puzzle me are the advancing directions of the occultations across the moon described in the article.
It said when the occultation occurs as the moon is in the waxing gibbous phase, Aldebaran would disappear behind the moon's dark limb and afterwards reappear from behind the moon's bright limb (such as the occultation on Dec. 23, 2015), and when the occultation occurs as the moon is in the waning gibbous moon, Aldebaran would disappear behind the moon's bright limb and afterwards reappear from behind the moon's dark limb (such as the occultation on Oct. 18, 2016).
But I think according to the revolving direction of the moon the advancing directions should be opposite to the above statement. The moon is revolving Earth in the counterclockwise direction, so I think in its waxing gibbous phase, it advances with its bright limb as the front and dark limb as the back, so that its bright limb would cover Aldebaran followed by the emergence of Aldebaran from behind its dark limb, and in its waning gibbous phase, it advances with its dark limb as the front and bright limb as the back, so that its dark limb would cover Aldebaran followed by the emergence of Aldebaran from behind its dark limb.
So where am I wrong to deduce the advancing directions opposite to those described by the article?
It said when the occultation occurs as the moon is in the waxing gibbous phase, Aldebaran would disappear behind the moon's dark limb and afterwards reappear from behind the moon's bright limb (such as the occultation on Dec. 23, 2015), and when the occultation occurs as the moon is in the waning gibbous moon, Aldebaran would disappear behind the moon's bright limb and afterwards reappear from behind the moon's dark limb (such as the occultation on Oct. 18, 2016).
But I think according to the revolving direction of the moon the advancing directions should be opposite to the above statement. The moon is revolving Earth in the counterclockwise direction, so I think in its waxing gibbous phase, it advances with its bright limb as the front and dark limb as the back, so that its bright limb would cover Aldebaran followed by the emergence of Aldebaran from behind its dark limb, and in its waning gibbous phase, it advances with its dark limb as the front and bright limb as the back, so that its dark limb would cover Aldebaran followed by the emergence of Aldebaran from behind its dark limb.
So where am I wrong to deduce the advancing directions opposite to those described by the article?