Don't Miss the Ghostly 'Da Vinci Glow' Illuminating the Moon This Week.

The "Da Vinci Glow," a phenomenon discovered by Leonardo da Vinci in the 16th century, will be visible in the night sky this week. Earthshine, which illuminates the night 50 times brighter than a full moon, creates a ghostly image of a full moon between the horns of a crescent moon. The glow is visible only with the presence of a crescent moon and can be seen during the first and last days of the moon's orbit around Earth. It will be visible prior to the new moon on May 19 and for a few days following.