Lunar eclipses happen when the moon, Earth, and sun align just so. The Earth casts a shadow that can partially or totally blot out the moon.

During a gathering of astronomers at the American Astronomical Society Meeting, the scientists reached for the stars and made an animated short about a total eclipse of the sun that they were ...

SEE ALSO: Solar eclipse stamp changes when you touch it They've launched a special simulator, part of the broader Eclipse Megamovie Project, which will give a glimpse of what to expect on August 21.