See this sky time lapse, an array of time-lapse movies, each showing a single day, arranged chronologically, and playing in sync. http://www.youtube.com/watch?v=PNln_me-XjI&feature=youtu.be&hd=1 http://www.murphlab.com/2011/11/15/a-history-of-the-sky-for-one-year/ January 26, 2012