Backyard Astronomer - Delta College Public Radio Delta College Public Radio

Even to the unaided eye, the moon reveals round dark regions called "maria." Before the age of telescopes, people imagined these dark stretches as oceans of water. In reality, they are vast lava plains left behind by asteroid impacts.

At the beginning of the week of June 10, the moon appears as a crescent in the west after sunset. But each night, the moon will appear to slip a little farther back or eastward among the stars.

If you follow the arc to Arcturus and keep the curve going even farther down into the south, you’ll come to a fainter bluish star, Spica.

Observe the night sky long enough and you’re bound to see something strange that’s hard to identify. It’s easy to think of a UFO, but that doesn’t automatically mean it’s an alien spaceship.

In binoculars, look near the very center of the lunar disk for a large crater that seems to have a dark, smooth floor. This is Ptolemaeus, named for Claudius Ptolemy, an astronomer of ancient Greece. Two more large craters in a line below Ptolemaeus, Aphonsus and Arzachel, complete the chain.

The moon is "new" this week, which keeps the night sky dark enough to see more stars and deep sky wonders. One distinctive little springtime constellation to look for in the south is called Corvus, the Crow.