Utopia Planitia is a large plain within Utopia, the largest recognized impact basin on Mars and in the Solar System with an estimated diameter of 3,300 km (2,100 mi). It is the Martian region where the Viking 2 lander touched down and began exploring on September 3, 1976, and the Zhurong rover touched down on May 14, 2021, as a part of the Tianwen-1 mission. It is located at the antipode of Argyre Planitia, centered at 46.7°N 117.5°E. It is also in the Casius quadrangle, Amenthes quadrangle, and the Cebrenia quadrangle of Mars.
Degas is a rayed crater on Mercury at latitude 37.5 N, longitude 127 W. Its diameter is 54 kilometres (34 mi). It was named after the French impressionist painter Edgar Degas in 1979. The rays consist of light colored material blasted out during the crater's formation. Craters older than Degas are covered by the ray material, while younger craters are seen superimposed on the rays. Degas forms a crater pair with Brontë to the north. Both lie near the center of Sobkou Planitia.
Odin Planitia is a large basin on Mercury. It was named after the Norse god Odin in 1976 by the IAU. It was first observed in detail by Mariner 10. The plain is approximately 473 kilometers in diameter.
Suisei Planitia is a large area of smooth plains on Mercury, approximately 570 km wide. Ghost craters are unusual forms that occur in the Suisei Planitia. They are buried and rounded in profile, with only their rim crests rising above the surrounding smooth plains. It has been suggested that material forming Suisei Planitia is ejecta from the impact that formed Caloris Planitia. The name for this Planitia was approved in 1976 by the IAU.
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.
Mozart is a crater on Mercury, named by the IAU in 1976 after Austrian composer Wolfgang Amadeus Mozart.
Outflow channels are extremely long, wide swathes of scoured ground on Mars. They extend many hundreds of kilometers in length and are typically greater than one kilometer in width. They are thought to have been carved by huge outburst floods.
Praxiteles is a crater on Mercury. It is one of 110 peak ring basins 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.
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.
Aksakov is a crater on Mercury. It has a diameter of 174 kilometers. Its name was adopted by the International Astronomical Union (IAU) on April 24, 2012. Aksakov is named for the Russian author Sergey Aksakov, who lived from 1791 to 1859 C.E.
Holst is a crater on Mercury. Its name was adopted by the International Astronomical Union (IAU) on April 24, 2012.
Alver is a crater on Mercury. It has a diameter of 151.49 kilometers. Its name was adopted by the International Astronomical Union (IAU) on March 15, 2013. Alver is named for the Estonian poet Betti Alver.
Namatjira is a crater on Mercury. It has a diameter of 34 kilometers. Its name was adopted by the International Astronomical Union (IAU) on September 25, 2015. Namatjira is named for the Australian aboriginal artist Albert Namatjira.
Hollows are a landform on the planet Mercury, discovered during the MESSENGER mission that orbited the planet from 2011 to 2015.
Faulkner is a crater on Mercury. It has a diameter of 168 kilometres. Its name was adopted by the International Astronomical Union (IAU) on April 24, 2012. Faulkner is named for the American author William Faulkner.
Mearcair Planitia is a large plain on the planet Mercury. The name Mearcair is the Irish word for "Mercury", and the name was approved in 2017. It was first observed in detail by MESSENGER. It lies between the large crater Raditladi and the ancient Caloris basin.
Stilbon Planitia is a large plain on the planet Mercury. The name Stilbon is ancient Greek word for "Mercury", and the name was approved in 2017. It was first observed in detail by MESSENGER. It lies north of the Caloris basin, and is approximately 1550 kilometers long.
The rim of Catullus
Anaglyph of the pit in the center of the crater
Hollows in Catullus crater
