Ursa Major, the Greater Bear, is a northern constellation that includes the Big Dipper asterism. Ursa Major has been associated with a bear by many different cultures and its mythology may date back as far as 13,000 years ago. The two end stars in the bowl of the Big Dipper, Dubhe and Merak, are the "Pointers". They can be used to find Polaris (Alpha Ursa Minoris), the North Star, by drawing a line from Merak to Dubhe and extending it to Polaris. Ursa Major was cataloged by the Greek astronomer Ptolemy in the second century C.E. (Common Era). It is the third largest of today's 88 modern constellations, covering 1,280 square degrees of sky.