Bob Moler's Ephemeris Blog

This is Ephemeris for Friday, August 19th. Today the Sun will be up for 13 hours and 52 minutes, setting at 8:41, and it will rise tomorrow at 6:51. The Moon, at last quarter today, will rise at 12:32 tomorrow morning.

I’ve already talked about the three constellations whose bright stars mark the Summer Triangle: Vega in Lyra the harp, Deneb in Cygnus the swan, and Altair in Aquila the eagle. There are two small constellations near the south end of the triangle near Altair. These are Delphinus the dolphin and Sagitta the arrow. Delphinus is easily spotted, as it’s five or six stars appear as a tiny dolphin leaping out of the water. Sagitta appears as a very short arrow. An interesting sight can be spotted in binoculars near the tail end of Sagitta. It’s 7 stars in a nearly straight line, with a hook of four stars below the center of the line. It’s called The Coathanger. It’s even better if seen in a finder telescope, which inverts the image.

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

Finding the small constellations of Delphinus the dolphin and Sagitta the arrow among the stars and constellations of the Summer Triangle. Created using Stellarium and GIMP.

How to locate the binocular asterism of the Coathanger. It is also known as Collinder 399, Brocchi’s Cluster and Al Sufi’s Cluster. It’s not a real star cluster, but a random arrangement of stars at various distances, that from the solar system make a distinctive pattern.