Caloris Planitia is a plain within a large impact basin on Mercury, informally named Caloris, about 1,550 km (960 mi) in diameter. It is one of the largest impact basins in the Solar System. "Calor" is Latin for "heat" and the basin is so-named because the Sun is almost directly overhead every second time Mercury passes perihelion. The crater, discovered in 1974, is surrounded by the Caloris Montes, a ring of mountains approximately 2 km (1.2 mi) tall.
The geology of Mercury is the scientific study of the surface, crust, and interior of the planet Mercury. It emphasizes the composition, structure, history, and physical processes that shape the planet. It is analogous to the field of terrestrial geology. In planetary science, the term geology is used in its broadest sense to mean the study of the solid parts of planets and moons. The term incorporates aspects of geophysics, geochemistry, mineralogy, geodesy, and cartography.
Tir Planitia is a large plain on the planet Mercury. The name Tir (تیر) is the Persian word for "Mercury",, and the name was approved in 1976. It was first observed in detail by Mariner 10. It lies between the large crater Mozart and the ancient Tolstoj basin.
The Borealis quadrangle is a quadrangle on Mercury surrounding the north pole down to 65° latitude. It was mapped in its entirety by the MESSENGER spacecraft, which orbited the planet from 2008 to 2015, excluding areas of permanent shadow near the north pole. Only approximately 25% of the quadrangle was imaged by the Mariner 10 spacecraft during its flybys in 1974 and 1975. The quadrangle is now called H-1.
Goethe Basin is an impact basin at 81.4° N, 54.3° W on Mercury approximately 317 kilometers in diameter. It is named after German poet Johann Wolfgang von Goethe.
The Tolstoj quadrangle in the equatorial region of Mercury runs from 144 to 216° longitude and -25 to 25° latitude. It was provisionally called "Tir", but renamed after Leo Tolstoy by the International Astronomical Union in 1976. Also called Phaethontias.
Tolstoj is a large, ancient impact crater on Mercury. It was named after Leo Tolstoy by the IAU in 1976. The albedo feature Solitudo Maiae appears to be associated with this crater.
The Shakespeare quadrangle is a region of Mercury running from 90 to 180° longitude and 20 to 70° latitude. It is also called Caduceata.
Beethoven is a crater at latitude 20°S, longitude 124°W on Mercury. It is 630 km in diameter and was named after Ludwig van Beethoven. It is the eleventh largest named impact crater in the Solar System and the third largest on Mercury.
Mozart is a crater on Mercury, named by the IAU in 1976 after Austrian composer Wolfgang Amadeus Mozart.
The Pantheon Fossae are a radial set of troughs in a region in the middle of Caloris Basin on Mercury. They appear to be a set of graben formed by extensional faults, with a 40 km crater located near the center of the pattern. The exact origin of this pattern of troughs is not currently known. The feature was nicknamed "the Spider" before receiving its official name.
Atget crater is distinctive on the planet Mercury's surface due to its dark color. Atget crater is located within Caloris basin, near Apollodorus crater and Pantheon Fossae. The dark color of the floor of Atget is in contrast to other craters within Caloris basin that exhibit bright materials on their floors, such as the craters Kertész and Sander. Other craters on Mercury, such as Bashō and Neruda, have halos of dark material but the dark material does not cover the crater floors.
Rembrandt is a large impact crater on Mercury. With a diameter of 716 km it is the second-largest impact basin on the planet, after Caloris, and is one of the larger craters in the Solar System. It was discovered by MESSENGER during its second flyby of Mercury on October 6, 2008. The crater is 3.9 billion years old, and was created during the period of Late Heavy Bombardment. The density and size distribution of impact craters along Rembrandt's rim indicate that it is one of the youngest impact basins on Mercury.
Moody is an impact crater on Mercury.
Raditladi is a large impact crater on Mercury with a diameter of 263 km. Inside its peak ring there is a system of concentric extensional troughs (graben), which are rare surface features on Mercury. The floor of Raditladi is partially covered by relatively light smooth plains, which are thought to be a product of the effusive volcanism. The troughs may also have resulted from volcanic processes under the floor of Raditladi. The basin is relatively young, probably younger than one billion years, with only a few small impact craters on its floor and with well-preserved basin walls and peak-ring structure. It is one of 110 peak ring basins on Mercury.
Scarlatti is a pit-floored crater on Mercury, which was discovered in 1974 by the Mariner 10 spacecraft. It has a prominent peak ring, and it is one of 110 peak ring basins on Mercury. The crater floor is covered by the smooth plains material. The crater displays an arcuate collapse feature along the northeastern peak ring. The size of the pit, which was first noticed in MESSENGER images obtained in January 2008, is 38 × 12 km. Such a feature may have resulted from collapse of a magma chamber underlying the central peak ring complex of the crater. The collapse feature is an analog of Earth's volcanic calderas. Scarlatti is thought to have the same age as the Caloris basin.
Rachmaninoff is an impact crater on Mercury. This basin, first imaged in its entirety during MESSENGER's third Mercury flyby, was quickly identified as a feature of high scientific interest, because of its fresh appearance, its distinctively colored interior plains, and the extensional troughs on its floor. The morphology of Rachmaninoff is similar to that of Raditladi, which is one of the youngest impact basins on Mercury. The age of Raditladi is estimated at one billion years. Rachmaninoff appears to be only slightly older.
Derain is a crater on Mercury named after André Derain, a French artist, painter, sculptor and co-founder of Fauvism with Henri Matisse. It has uncommonly dark material within and surrounding the crater. The material is darker than the neighboring terrain such that this crater is easily identified even in a distant global image of Mercury. The dark halo may be material with a mineralogical composition different from the majority of Mercury's visible surface. Craters with similar dark material on or near their rims were seen on the floor of the Caloris basin during MESSENGER’s first flyby.
Ghost craters on the planet Mercury have tectonic features such as graben and wrinkle ridges. These features were formed by extensional and contractional forces originating in tectonic processes such as uplift and global contraction. The combination of graben and wrinkle ridges inside ghost craters found on Mercury has not been observed on any of the other terrestrial planets.
Inter-crater plains on Mercury are a land-form consisting of plains between craters on Mercury.
