Scheduled time for Public Observing: 8pm – 10pm

Solar System Objects:

The Moon: will be 78% illuminated. The major maria or “seas” are labeled on the image below. The Apollo 15 landing site is on the edge of Mare Imbrium, but anything left behind is far too small to be seen in any telescope. It has been imaged by the Lunar Reconnaissance Orbiter, however, click here to see the picture. It was the first mission to use the Lunar Rover.

Image copyright (c) Virtual Moon Atlas /

Crater of the month: Tycho is possibly the most prominent crater on the moon, not because of it’s size (85 km in diameter), but because of it’s bright ray system that extends across the entire face of the moon. At 108 million years old the bright streaks, caused by ejecta from the impact, haven’t yet had time to fade away. See more detailed photos from NASA here.


Mars will be the only planet visible tonight. The switch to Daylight Saving Time does us a favor by keeping Mars above 20 degrees altitude for observation until 9:40 pm, after which it will be too low in the sky and the image will be blurry. Mars is quite distant from us now at 177 million miles, 1.9 times farther than the sun, and will appear only 4.9 arc seconds in diameter.

Deep-Sky Objects:

Nebula and Star Clusters: Even with moonlit skies there are a few open clusters (M35, 36, 37, and 38), and a planetary nebula (NGC 2392, the Eskimo Nebula) that could still be observable, especially if the transparency of the atmosphere is good. M42, the Orion Nebula, is a star-forming region that’s visible under all but the worst circumstances.

Double Stars: Are interesting to observe in a telescope, a couple of the brightest this time of year are Castor in Gemini and Gamma Leonis.

Star Charts and other Information:

A very useful monthly star chart can be downloaded here from, giving information on objects visible with the unaided eye, binoculars, or telescope.

For current astronomical events see Sky and Telescope Magazine’s “This Week’s Sky at a Glance”.