Astronomy Picture of the Day . ... Julius Caesar and Leap Days . ... X-ray Moon and X-ray Star . ... An X-ray star winks out behind the Moon in these before and after views of a lunar occultation of the galactic X-ray source designated GX5-1. ... Apollo 15: Driving on the Moon . ... Apollo 15's Home on the Moon . ... The lunar module shown above, named "Falcon," served as home for Apollo 15 astronauts David Scott and James Irwin during their stay on the Moon in July and August 1971. ...