juneborn: A year over the Pacific, photographed by GOES-15, 2012-2013.
24 frames, photographed at at the same time of day (0300 UTC) on the 7th and 22nd of each month from June 2012 to June 2013 (one year, solstice-to-solstice). 2nd gif rearranges the frames to keep the angle of sunlight constant.
This is the effect caused by the fixed tilt of Earth’s axis and Earth’s orbit around the Sun; you can see the periods when the poles experience day or night for months at a time - this is when the poles are tilted toward and away from the Sun, respectively.
Image credit: NOAA/NASA, via NCDC/GIBBS. Animation: AgeOfDestruction.