During a total lunar eclipse, red wavelengths of sunlight pass through Earth’s atmosphere and reach the Moon, earning it the nickname Blood Moon. A partial lunar eclipse occurs when only a portion of the Moon enters Earth's umbra, making part of the Moon dark while the rest remains illuminated.

Learn about the types, causes and effects of lunar eclipses, when Earth's shadow falls on the moon. Find out how to observe and photograph this popular skywatching event with or without a telescope.

Learn how the Moon's appearance changes over the month and why it sometimes disappears or turns red. Find out how to observe and understand lunar eclipses, and how they affect spacecraft.

Learn how lunar eclipses happen when the sun, Earth, and moon align, and what causes the different types: total, partial, and penumbral. Discover how ancient cultures interpreted these cosmic events and why they are becoming rarer.

Learn what a lunar eclipse is, how it occurs, and why it makes the Moon turn red. Find out when and where to see the next lunar eclipse and how to distinguish it from a solar eclipse.

Learn what a lunar eclipse is, how it happens, and why the moon sometimes turns red. Explore the scientific facts and visualizations of this natural phenomenon with the Exploratorium.

Learn how a lunar eclipse happens when the full Moon enters the Earth's shadow and turns red. Find out when the next lunar eclipse will be visible from the western hemisphere and how to observe it.

Learn how a lunar eclipse happens when the Moon passes through the Earth's shadow and why it can turn red. Watch a video animation and download high-quality files from NASA's Goddard Space Flight Center.

Learn about lunar and solar eclipses, how they occur, and what they look like. Find out when and where you can see the next eclipses and how to observe them safely.