Mare Nectaris is a small lunar mare or sea located south of Mare Tranquillitatis southwest of Mare Fecunditatis, on the near side of the moon. Montes Pyrenaeus borders the mare to the east and Sinus Asperitatis fuses to its northwestern edge. It is 84,000 square kilometers in size.
Alphonsus is an ancient impact crater on the Moon that dates from the pre-Nectarian era. It is located on the lunar highlands on the eastern end of Mare Nubium, west of the Imbrian Highlands, and slightly overlaps the crater Ptolemaeus to the north. To the southwest is the smaller Alpetragius.
Copernicus is a lunar impact crater located in eastern Oceanus Procellarum. It was named after the astronomer Nicolaus Copernicus. It typifies craters that formed during the Copernican period in that it has a prominent ray system. It may have been created by debris from the breakup of the parent body of asteroid 495 Eulalia 800 million years ago.
Fermat is a lunar impact crater located to the west of the Rupes Altai escarpment. To the west-southwest is the larger crater Sacrobosco, and to the southwest is the irregular Pons. It is 39 kilometers in diameter and two kilometers deep.
Fra Mauro is the worn remnant of a walled lunar plain. It is part of the surrounding Fra Mauro formation, being located to the northeast of Mare Cognitum and southeast of Mare Insularum. Attached to the southern rim are the co-joined craters Bonpland and Parry, which intrude into the formation forming inward-bulging walls. The crater is named after Italian geographer Fra Mauro.
Eratosthenes crater is a relatively deep lunar impact crater that lies on the boundary between the Mare Imbrium and Sinus Aestuum mare regions. It forms the western terminus of the Montes Apenninus mountain range. It is named after ancient Greek astronomer Eratosthenes of Cyrene, who estimated the circumference of the Earth, and the distance from the Earth to the Sun.
Ptolemaeus is an ancient lunar impact crater close to the center of the near side, named for Claudius Ptolemy, the Greco-Roman writer, mathematician, astronomer, geographer and astrologer. It measures approximately 154 kilometers in diameter.
Thebit is a lunar impact crater located on the southeast shore of Mare Nubium. To the north-northwest is the crater Arzachel, and Purbach lies to the south-southwest. To the southwest is the flooded remnants of Thebit P, which is actually larger in diameter than Thebit itself.
Schiller is a lunar impact crater located in the southwestern region of the Moon's near side. The rim of Schiller has an elongated shape that is amplified by its proximity to the lunar limb. The long axis lies along a line running northwest–southeast, with the wider girth located in the southeastern half. There is a slight bend in the elongation, with the concave side facing to the northeast. Schiller is thought to be a fusion of two or more craters.
Birt is a lunar impact crater located in the eastern half of the Mare Nubium and west of the Rupes Recta. It was named after British selenographer William R. Birt.
Catharina is an ancient lunar impact crater located in the southern highlands. It was named after Saint Catherine of Alexandria. It lies in a rugged stretch of land between the Rupes Altai scarp to the west and Mare Nectaris in the east. To the west-northwest is the crater Tacitus, and the lava-flooded Beaumont lies to the east along the shore of Mare Nectaris. To the south-southeast is Polybius.
Deslandres is the heavily worn and distorted remains of a lunar impact crater. It is located to the southeast of the Mare Nubium, in the rugged southern highlands of the Moon. In dimension it is the third-largest crater formation on the visible Moon, being beaten only by Clavius and by the 303-kilometer-diameter walled plain Bailly. The northern and eastern parts of the floor display a relatively level surface, but it is pock-marked with numerous craters. There is a small region of mare material, due to basaltic lava, along the eastern interior floor.
Petavius is a large lunar impact crater located to the southeast of the Mare Fecunditatis, near the southeastern lunar limb. Attached to the northwest rim is the smaller crater Wrottesley. To the southeast are Palitzsch, Vallis Palitzsch, and Hase. Farther to the north is the large crater Vendelinus. Petavius appears oblong when viewed from the Earth due to foreshortening. Petavius is Imbrian in age.
Triesnecker is a prominent lunar impact crater that is located in the Sinus Medii, near the central part of the Moon's near side. Its diameter is 25 km. It was named after Austrian astronomer Franz de Paula Triesnecker. It is located to the north-northwest of the crater Rhaeticus, and to the east-southeast of the flooded Murchison.
Abulfeda is a lunar impact crater located in the central highlands of the Moon. To the northeast is the crater Descartes, and to the south-southeast is Almanon. To the north is the crater Dollond. A chain of craters named the Catena Abulfeda runs between the southern rim of Abulfeda and the north rim of Almanon, then continues for a length of 210 kilometers across the Rupes Altai. The crater was named for 14th century Kurdish historian Ismael Abul-fida.
Julius Caesar is a lava-flooded lunar impact crater with a low, irregular, and heavily worn wall. Its diameter is 85 km. It was named after Roman statesman Julius Caesar. It is located to the west of Mare Tranquillitatis, and directly southeast of the crater Manilius on the Mare Vaporum. To the east is the rounded Sosigenes.
Buys-Ballot is an oddly-shaped lunar impact crater that is located on the far side of the Moon. It lies just to the northwest of the small lunar mare named Lacus Luxuriae, and southeast of the crater Freundlich. Other nearby craters of note are Anderson to the southwest and Dante to the northeast.
J. Herschel is a large lunar impact crater of the variety termed a walled plain crater. The crater is named after British astronomer John Herschel. It is located in the northern part of the Moon's surface, and so appears foreshortened when viewed from the Earth. The southeastern rim of J. Herschel forms part of the edge of the Mare Frigoris lunar mare. To the northwest is the crater Anaximander. Bordering the northern rim is a large, unnamed lunar plain. Just to the south is the small crater Horrebow.
Rupes Recta is a linear fault on the Moon, in the southeastern part of the Mare Nubium at 22.1°S 7.8°W. The name is Latin for straight cliff, although it is more commonly called the Straight Wall. This is the most well-known escarpment on the Moon, and is a popular target for amateur astronomers.
Rupes Cauchy is a 120 km-long escarpment at 9.0°N 37.0°E on the surface of the Moon. It faces southwest, and rises about 200–300 m. It is located in the northeastern portion of the Mare Tranquillitatis, and is named after the nearby crater Cauchy.
