Mercury is the first planet from the Sun and the smallest in the Solar System. In English, it is named after the Roman god Mercurius (Mercury), god of commerce and communication, and the messenger of the gods. Mercury is classified as a terrestrial planet, with roughly the same surface gravity as Mars. The surface of Mercury is heavily cratered, as a result of countless impact events that have accumulated over billions of years. Its largest crater, Caloris Planitia, has a diameter of 1,550 km (960 mi) and one-third the diameter of the planet. Similarly to the Earth's Moon, Mercury's surface displays an expansive rupes system generated from thrust faults and bright ray systems formed by impact event remnants.
Chao Meng-Fu is a 167 km (104 mi) diameter crater on Mercury named after the Chinese painter and calligrapher Zhao Mengfu (1254–1322). Due to its location near Mercury's south pole and the planet's small axial tilt, an estimated 40% of the crater lies in permanent shadow. This combined with bright radar echoes from the location of the crater leads scientists to suspect that it may shelter large quantities of ice protected against sublimation into the near-vacuum by the constant −171 °C (−276 °F) temperatures.
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.
Sobkou Planitia is a large basin on the planet Mercury. It is named after the ancient Egyptian messenger deity Sobkou. He was associated by the Egyptians with the planet Mercury.
Sholem Aleichem is a crater on Mercury, named after the Yiddish writer Sholem Aleichem. The inter-crater plain deposits have been deformed by linear ridges.
Vyāsa is a crater on Mercury. It was named by the IAU in 1979, after the Indian poet Vyasa.
Verdi is an impact crater on the planet Mercury. It was named after Italian Romantic composer Giuseppe Verdi (1813–1901) in 1979, as recognized by the International Astronomical Union. The crater's extensive ejecta blanket and secondary crater field are superposed on plains materials and older craters.
Hokusai is a rayed impact crater on Mercury, which was discovered in 1991 by ground-based radar observations conducted at Goldstone Observatory. The crater was initially known as feature B. Its appearance was so dissimilar to other impact craters that it was once thought to be a shield volcano. However improved radar images by the Arecibo Observatory obtained later in 2000–2005 clearly showed that feature B is an impact crater with an extensive ray system. The bright appearance of rays in the radio images indicates that the crater is geologically young; fresh impact ejecta has a rough surface, which leads to strong scattering of radio waves.
Debussy is a rayed impact crater on Mercury, which was discovered in 1969 by low resolution ground-based radar observations obtained by the Goldstone Observatory. Later in 1990–2005 it was imaged in more detail by the Arecibo Observatory. The crater was initially known as the feature A. The bright appearance of rays in the radar images indicates that the crater is geologically young, because fresh and rough surfaces of young impact craters are good scatterers of radio waves.
Copland is an impact crater on Mercury. Its floor is flooded with volcanic smooth plains material, which could be related to the activity that formed the nearby bright vent known as Nathair Facula.
Al-Hamadhani is a crater on Mercury. It has a diameter of 186 kilometers. Its name was adopted by the International Astronomical Union in 1979. Al-Hamadhani is named for the Iranian writer Badi' al-Zaman al-Hamadani, who died in 1007 C.E.
Bruegel is a crater on Mercury. It has a diameter of 72 kilometers. Its name was adopted by the International Astronomical Union in 1985. Bruegel is named for the Flemish painter Pieter Bruegel the Elder, who lived from 1525 to 1569.
Chekhov is a crater on Mercury. It has a diameter of 194 kilometers. Its name was adopted by the International Astronomical Union (IAU) in 1976. Chekhov is named for the Russian author Anton Chekhov, who lived from 1860 to 1904.
Dürer is a crater on Mercury. It has a diameter of 195 kilometers. Its name was adopted by the International Astronomical Union (IAU) in 1976. Durer is named for the German artist Albrecht Dürer, who lived from 1471 to 1528.
Equiano is a crater on Mercury. It has a diameter of 102 kilometers. Its name was adopted by the International Astronomical Union in 1976. Equiano is named for the abolitionist writer Olaudah Equiano, who lived from 1750 to 1797.
Futabatei is a crater on Mercury. It has a diameter of 57 kilometers. Its name was adopted by the International Astronomical Union in 1976. Futabatei is named for the Japanese novelist Futabatei Shimei, who lived from 1864 to 1909.
Lysippus is a crater on Mercury. Its name was adopted by the International Astronomical Union in 1976. Lysippus is named for the Greek sculptor Lysippos, who lived in the 4th century BCE.
Ma Chih-Yuan is a crater on Mercury. Its name was adopted by the International Astronomical Union (IAU) in 1976. Ma Chih-Yuan is named for the Chinese playwright Ma Zhiyuan, who lived in the 13th century CE.
Enheduanna is a crater on Mercury. It has a diameter of 105 kilometers. Its name was suggested by Gagan Toor from India in a naming contest which was eventually adopted by the International Astronomical Union (IAU) on 2015. Enheduanna is named for the Sumerian poet Enheduanna. The craters Carolan, Kulthum, Karsh, and Rivera were also named as part of the contest.
