Suggested Searches

APOD

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

A full Moon is shown but with a much more detailed surface than is usually visible. Many craters, dark lunar mare, and light lunar highlands are discernable. Please see the explanation for more detailed information.A full Moon is shown but with a much more detailed surface than is usually visible. Many craters, dark lunar mare, and light lunar highlands are discernable. Please see the explanation for more detailed information.

Terminator Moon: A Moonscape of Shadows

Explanation: What's different about this Moon? It's the terminator s. In the featured image, you can't directly see any terminator -- the line that divides the light of day from the dark of night. That's because the featured image is a digital composite of many near-terminator lunar strips over a full Moon . Terminator regions show the longest and most prominent shadow s -- shadows which, by their contrast and length, allow a flat photograph to appear three-dimensional . The overlay images were taken over two weeks in early April. Many of the Moon's craters stand out because of the shadow s they all cast to the right. The image shows in graphic detail that the darker regions known as maria are not just darker than the rest of the Moon -- they are also flatter .

Dial-A-Moon: Find the Moon phase on your birthday this year

Date April 22, 2025
Credit Image Credit & Copyright: Rich Addis
Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
A service of: ASD at NASA / GSFC,
NASA Science Activation & Michigan Tech. U.