Carl Sagan's Cosmic Calendar, in which the entire 13.75 billion-year history of the universe is scaled down to a single year. At this scale, the Earth formed in August, life arose in September, and the first land plants appeared in mid-December. Apes did not appear until the very last day of the year. The first humans show up in the last six minutes and civilization in the final 30 seconds.
2017 Astronomical Events Check out our calendar of some of 2017's astronomical events for sky watchers. Most of these natural occurrences can be observed with the naked eye but use a pair of binoculars or a telescope for best viewing.