In this July 1997 still frame captured from video, the bright star Aldebaran has just reappeared on the dark limb of the waning crescent moon in this predawn occultation.

An occultation is an event that occurs when one object is hidden by another object that passes between it and the observer. A planet, for example, can pass in front of a star. Some occultations are eclipses. The word is often used in astronomy. It can also be used in a non-astronomical sense to describe when an object in the foreground occults (covers up) objects in the background.

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