A bright star will disappear for up to an hour tonight — here's what's happening

Night sky image showing a bright blue star in the center, surrounded by thousands of smaller stars ranging from yellow, orange, blue and white in color.

If you live in the middle Atlantic or southeast part of the United States, you'll have an opportunity tonight (April 25), to see a 70% illuminated waxing gibbous moon gradually drift toward and ultimately hide the 1st-magnitude star, Regulus, the brightest star of the constellation Leo the Lion.

This event is called an occultation, a word that is derived from the Latin occultāre, which means literally "to conceal." And if you are fortunate enough to live in the zone of visibility for this event (see below), that's exactly what you will see on Saturday evening: the moon, appearing to temporarily conceal Regulus from your view.