(from the article `astronomical map`) Two other astronomical reference systems developed independently in early antiquity, the lunar mansions and the Egyptian decans. The decans are 36 ... ...of which consists of 30°; in this they followed the Babylonians. They further regarded each of these 12 signs as the domicile (or house) of a ... Found on http://www.britannica.com/eb/a-z/d/22