Watch the moon cover up the blue giant star Spica on July 13

The outline of an orange circle floats in the center of a black, starry sky, its top and bottom to massive to fit in frame. In the center, a bright star Spica shoots out three blue lines diagonally left and right, and one upward slightly right. A quarter moon shines to the right of Spica.

One of the most interesting events in visual astronomy, and certainly the fastest, occurs when the moon occults a star. The moon's edge creeps up to it, seems almost to press against it for a number of seconds, and then suddenly the star is gone! It reappears just as abruptly on the moon's other side up to an hour or more later. 

On Saturday (July 13) anyone with a telescope and a clear sky should be concentrating on that evening's moon, just past the first quarter (52% illuminated). That will be when the moon will pass in front of the 1st-magnitude star Spica as seen from North America.