How Eclipses Work

Crescent eclipse behind windmills
On May 20, 2012, the Sun set while in deep partial eclipse as seen from the U.S. Southwest. This scene was captured from the San Juan Mesa Wind Farm off Highway 70 in Elinda, New Mexico.

Photo courtesy of the American Astronomical Society / Evan Zucker

Eclipse events occur when the sun, moon, and earth are in line, blocking the sunlight or casting a shadow. Learn about how and when solar and lunar eclipses happen, as well as how people interpret eclipse events and nature’s responses.

Last updated: March 9, 2017