Analemma (3-year time-lapse)

Time-lapse of the Sun in the West, one picture every 24 hours: the solar analemma. Watch as the Sun traces out a figure 8 in the sky each year from 2015 to 2018. Why does the position of the Sun change day-to-day? The Earth spins about its axis at about a 23.5 degree angle to its orbital axis around the Sun, and the Earth orbits the Sun in an ellipse, moving faster when closer to the Sun. The result is that the position of the Sun in the sky changes not just minute by minute as the Earth rotates, but day to day as well as the Earth moves through its orbit. The figure 8 path traced out by the Sun when viewed in 24 hour increments is known as the solar analemma. This video was made from a series of pictures that were each taken 24 hours apart by the HPWREN cameras at the Mount Laguna Observatory in San Diego County over a 3 year period. See also a time-lapse movie showing when and where the Sun sets on the horizon each day of the year: Playlist with additional time-lapse astronomy videos: