This map depicts the Moon as it will appear from the Southern Hemisphere on October 1, 2022, the date of International Observe the Moon Night. Many of the best views will occur along the terminator (the line between the day and night side of the Moon).
The "Sea of Cold" is located in the outer rings of the huge, flat region called Oceanus Procellarum. Fairly faint, it’s best viewed at full moon, but the eastern half is visible on International Observe the Moon Night.
Mare Serenitatis (Sea of Serenity)
Basalt covers a majority of this mare, which features the crater Posidonius on its northeast rim. Apollo 17 astronauts landed near the eastern edge of the Sea of Serenity on December 17, 1972.
Mare Crisium (Sea of Crises)
The Sea of Crises, location of the 1976 Soviet sample return mission Luna 24, covers over 109,000 square miles (176,000 km) of the lunar surface ― about the size of Nevada.
Mare Tranquillitatis (Sea of Tranquility)
Famous for being the site of the Apollo 11 landing and moonwalk, the Sea of Tranquility is rich in metals, including titanium, thought to be created when an ocean of magma that once covered the surface crystallized.
Mare Fecunditatis (Sea of Fertility)
The Sea of Fertility impact basin was the site of the first automated sample return, taken by the Soviet Luna 16 probe in 1970. This mare is a little over 500 miles (804 km) in diameter but less visually distinct than other, similarly sized lunar mare.
Mare Humboldtianum (Humboldt’s Sea)
This mare was named after German naturalist and explorer Alexander von Humboldt (1769-1859) and is one of only two maria named after people. The moon’s wobble, called libration, can sometimes hide the sea from view.
Mare Smythii (Smyth’s Sea)
One of the youngest impact basins, Smyth’s Sea has an average depth of about 3 miles (5 km) below the surrounding surface and some unusually dark lava surfaces. The second mare named after a person, it references British astronomer William Henry Smyth (1788-1865).
“Lake of Death," is a lava plain about 100 miles (160 km) across. It was chosen as a landing site for NASA’s Commercial Lunar Payload Services program. Near the lava plain's center is the crater Burg, 25 miles (40 km) in diameter. West of Burg, Lacus Mortis’ floor is broken by a fascinating network of fractures and ridges.
Rima Ariadaeus (Ariadaeus Rille)
This is one of the Moon’s best examples of a channel-like dent in the lunar crust, called a straight rille. Running roughly east to west, it appears as a great fracture, measuring about 136 miles (220 km) long, 2.5 miles (4 km) wide, and 0.5 miles (0.8 km) deep. It's an example of a graben, where a long block of land drops down between two parallel faults. It may have been formed by rising magma wedging open a crack in the lunar crust.
Messier Crater
This young, small crater is oblong in shape, measuring 6 by 9 miles across (10 by 15 km). About 14 miles (23 km) to its west, along the line of Messier’s long axis, is a similarly sized crater, Messier A. Continuing over 62 miles (100 km) to the west from Messier A is a pair of bright rays of pulverized, ejected rock. The crater shapes, their orientation, and the highly directional ejecta indicate this pattern was formed by an impacting asteroid skimming in at a very low angle.
Theophilus, Cyrillus, & Catharina Craters
This prominent trio of craters with similar sizes (62 mile or 100-km diameters) but different ages illustrates how lunar craters degrade over time. Theophilus, the youngest and northernmost, has well-preserved terraced walls, a flat floor, and central peaks. Cyrillus’ northeast wall is breached by Theophilus. Catharina is oldest, scarred by later impacts.
Rupes Altai (Altai Scarp)
This spectacular cliff face is formed by the southwestern rim of an outer ring of the multi-ring Nectaris impact basin, which is partly filled by the lava plains of Mare Nectaris to the northeast. The scarp reaches about 2.5 miles (4 km) in height and traces a curving path roughly 310 miles (500 km) long.
Vallis Rheita (Rheita Valley)
This long, deep trough stretches over 250 miles (400 km), reaches more than 18.6 miles (30 km) width, and is more than 1.5 miles (2.5 km) deep. A clue to its origin comes from its orientation, pointing outward from the Nectaris impact basin. The valley is actually an overlapping chain of secondary impact craters formed by debris violently blasted out from the great Nectaris impact. The Rheita Valley is the most prominent of many similar scars in this area.
The first human landing site was on the smooth, flat plains of Mare Tranquillitatis (Sea of Tranquility). The region was selected because it is relatively smooth and flat ― but even so, astronauts Armstrong and Aldrin had to maneuver their lander during the last minutes of their descent in order to avoid a field of giant boulders.
Apollo 16
This was the first and only mission to land in the rugged lunar highlands. In April 1972, astronauts Young and Duke collected rock samples more than 4 billion years old. These showed that the ancient lunar crust formed from rock that crystallized and floated to the top of a global lunar magma ocean.
Apollo 17
The final Apollo mission to land on the Moon visited the spectacular Taurus-Littrow Valley, deeper than Earth’s Grand Canyon. In December 1972, astronauts Cernan and Schmitt (the first professional geologist on the Moon) explored an active fault scarp, a gigantic landslide deposit, and brought back samples including beads of volcanic glass erupted in an ancient lunar fire fountain.
Note: Detailed images are from NASA's Lunar Reconnaissance Orbiter. Find more high-resolution images of the Moon at NASA's MoonTrek.
