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.
2026 April 22
Explanation: What does it mean for the Earth to set? Artemis II Commander Reid Wiseman gave us another spectacular view of Earth from their historic flyby of the Moon. Commander Wiseman's video, taken with an iPhone at 8x zoom, shows our entire planet gradually blocked from view by the Moon. On the Earth, the 24-hour planetary rotation causes the Sun to set below your horizon every night. However, on Artemis II the Earthset was caused not by the Moon’s rotation but by the spacecraft moving behind the Moon (at about 55 seconds in this video). Once rare, views of Earth are now taken many times a day from many spacecraft, including NASA’s SWOT (Surface Water and Ocean Topography) satellite tracking freshwater resources and USGS Landsat 8 and 9 satellites supporting water management for farmers, for example. Space agencies around our home planet now work together to provide unique and ever-improving views of our Earth.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell (UMCP)
NASA Official: Amber Straughn
Specific rights apply.
NASA Web Privacy,
Accessibility,
Notices;
A service of:
ASD at
NASA /
GSFC,
NASA Science Activation
& Michigan Tech. U.