With a small telescope, craters along the terminator of the moon should be visible after sunset this week.

Courtesy of Tim Hunter

Moon Watch

The moon is a thin waning (growing smaller) crescent. New moon is Friday, June 23, and Saturday night you may be able to see the one-day-old crescent moon. You will need clear skies and a clear western horizon. Look for it six degrees above the horizon starting just after sunset (7:34 p.m.). Binoculars will help you spot the moon which sets at 8:17 p.m. On Monday night, the two-day-old crescent moon will be considerably easier to find above the western horizon after sunset.

Hercules

Now is a good time for viewing a stellar hero. Hercules the Hero is on his side, 60-70 degrees above the eastern horizon around 9 p.m. The body of Hercules is a misshapen square of four stars. Stars extending north and south from both sides of his body represent his arms and legs.

Hercules is not one of the brighter constellations but is easily seen on a reasonably dark night. Along the western side of the “square” portion of Hercules, toward the northwest corner of the square, is a faint density visible in a dark sky to the unaided eye.

Through a small telescope, this density reveals itself to be a compact ball of thousands of stars, a globular cluster named M13, the 13th object described in a famous catalog of non-stellar objects complied by the French astronomer Charles Messier (1730-1817) in the 18th century. M13 is a favorite object of amateur astronomers both for viewing and photography. It is about 25,100 light years away and contains several hundred thousand stars.