                        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.

                                2026 April 22

                           Earthset with an iPhone
                      Video Credit: NASA, Reid Wiseman
         Text: Keighley Rockcliffe (NASA GSFC, UMBC CSST, CRESST II)

   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.

                            Celebrate: Earth Day
                       Tomorrow's picture: placeholder
     __________________________________________________________________

       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.

