Nine Day Old Moon‡

The Waxing Gibbous Moon will be visible during the late afternoon, setting more than an hour after midnight. It transits around mid-evening, which makes observing ideal on this night, as one may view through the least atmosphere in dark skies without requiring a late night of observing.


Key Features to Observe Tonight

Tonight the westward movement of the terminator has revealed the magnificent ring mountain crater Copernicus. Due to its relatively isolated location and brightness against the dark mare, it stands out quite prominently.

Beginning in the Northern regions, the long, ribbon of the Mare Frigoris continues to be revealed. South of it, the distinctive, deep dark circle of Plato marks the northern shore of Mare Imbrium. The peaks of the Teneriffe Mountains are seen just below its northern rim. They appear to be remains of the tallest summits of the mare's crater wall, now mostly submerged beneath the infilling lava of the mare.

To the east is the magnificent mountain range named the Apennine Mountains. They are so dazzling that they can be seen with the naked eye.

On the great plain of Mare Imbrium itself are several new features to view tonight. Just west of Timocharis seen first last night is the crater Lambert R. Due south of it, the small crater Pytheas stands out nicely against the dark lava. The Carpathian Mountains wrap the southern portion of the Mare Imbrium, forming its border. They represent the remains of the wall from the huge Imbrium impact.

Southwest of Copernicus by a couple of diameters, lies the smaller Reinhold, a nicely distinct crater with its smaller companion Reinhold B on its northeast slope. Just below it is the dark plain of Mare Cognitum, followed by Mare Nubium. Another two Crisium diameters further south, the slightly larger crater Bullialdus, with a large central peak, is unmistakable on the western end of the dark Mare Nubium. The very impressive ray crater Tycho continues to grow brighter as the Sun rises in the lunar sky.

Finally, south of Tycho, one sees the huge walled plain Clavius, which is the second largest nearside crater. It is another favorite of lunar observers. Careful observation reveals that its floor is convex. A series of six diminishing sized craters runs in a pleasant arc from the south to the west across its floor.


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