Sixteen Day Old Moon‡

The Waning Gibbous Moon will be visible during the late afternoon, setting after dawn. It transits after midnight, which favors observing tonight, as one views through the least atmosphere in dark skies.


Key Features to Observe Tonight

Close to the northern lunar pole is the prominent dark oval of Endymion. The distinctive pair of craters Atlas and Hercules lie southwest of it, by a couple of times its diameter.

The entire Mare Crisium is visible for the last time, after tonight the terminator progressively covers it as it sweeps westward. Cleomedes a large, smooth crater, lies north of the circular Mare Crisium, which makes it easily recognizable. It is spectacular tonight. Two other craters near it show strongly: Geminus and the old walled plain Messala.

To the south of Mare Crisium by slightly more than its diameter is the sharp rimmed crater Langrenus. It shows strong relief in this light, very different from its appearance as a bright ring during the Full Moon. South of Langrenus by roughly its diameter is Vendelinus, slightly larger and with softened, degraded contours from long micrometer bombardment, indicating age. South of it, at a similar distance, lies Petavius, a ring mountain crater whose large multiple central peaks appear very nice tonight.


‡with permission from Lunar Discoverer User's Manual by Robert Duvall, 2013