Bob Moler's Ephemeris Blog

This is Ephemeris for Thursday, July 20th. Today the Sun will be up for 15 hours and 5 minutes, setting at 9:21, and it will rise tomorrow at 6:17. The Moon, 3 days past new, will set at 11:16 this evening.

Seen in high in the west-southwest at 10:30 this evening is the kite shaped constellation of Boötes (pronounced Bo-o-tees) the herdsman. The bright star Arcturus is at the bottom of the kite. It is pointed to by the arc of the handle of the Big Dipper, part of Ursa Major, the Great Bear, over toward the northwest. Boötes represents a young hunter named Arcas, son of Callisto, a beautiful young lady who had the misfortune of being loved by Zeus, the chief of the Greek gods. Zeus’ wife, Hera, found out about it, and since she couldn’t punish Zeus, turned the poor woman into a bear. Arcas, many years later, unaware of the events surrounding his mother’s disappearance, was about to kill the bear when Jupiter intervened and placed them both in the sky to save her. Arcas still pursues her across the sky nightly.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum