Probably because old calendars (such as the Persian Calendar) used 360 days for a year-when they watched the stars they saw them revolve around the North Star one degree per day.
September 27, 2015 will bring a supermoon lunar eclipse at nightfall. The last lunar eclipse of this magnitude occurred in 1982, and the next one of a similar magnitude will be in 2033. A lesser lunar eclipse will come in 2018. The lunar eclipse part of this phenomenon, according CTV, is caused by the Earth inserting itself between the sun and the moon. As this happens, the Earth casts its shadow on the face of the moon.
Another supermoon eclipse will not occur again until 2033. The total lunar eclipse will last about one hour and 12 minutes, according to NASA. It will be seen in North and South America, as well as Europe, Africa, parts of West Asia and the eastern Pacific.