Aristillus is a prominent lunar

impact crater An impact crater is a depression (geology), depression in the surface of a solid astronomical body formed by the hypervelocity impact event, impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal c ...

that lies in the eastern

Mare Imbrium Mare Imbrium (Latin ''imbrium'', the "Sea of Showers" or "Sea of Rains") is a vast lunar mare, lava plain within the Imbrium Basin on the Moon and is one of the larger craters in the Solar System. The Imbrium Basin formed from the collision ...

. It was named after Greek astronomer Aristyllus. Directly to the south is the smaller crater Autolycus, while to the southwest is the large

Archimedes Archimedes of Syracuse ( ; ) was an Ancient Greece, Ancient Greek Greek mathematics, mathematician, physicist, engineer, astronomer, and Invention, inventor from the ancient city of Syracuse, Sicily, Syracuse in History of Greek and Hellenis ...

. To the northeast are the craters Theaetetus and Cassini. The rim of Aristillus has a wide, irregular outer

rampart Rampart may refer to: * Rampart (fortification), a defensive wall or bank around a castle, fort or settlement Rampart may also refer to: * LAPD Rampart Division, a division of the Los Angeles Police Department ** Rampart scandal, a blanket ter ...

of ejecta that is relatively easy to discern against the smooth surface of the surrounding mare. The crater impact created a

ray system In planetary geology, a ray system comprises radial streaks of fine '' ejecta'' thrown out during the formation of an impact crater, looking somewhat like many thin spokes coming from the hub of a wheel. The rays may extend for lengths up to ...

that extends for a distance of over 600 kilometers. Due to its rays, Aristillus is mapped as part of the Copernican System. The rim is generally circular in form, but possesses a slight hexagonal shape. The inner walls of the rim have a terraced surface, and descend to a relatively rough interior that has not been flooded with lava. In the middle of the crater is a set of three clustered peaks, which rise to a height of about 0.9 km. In the northern outer

s of Aristillus is a ghost crater remnant. This is the protruding rim of an old crater that has been almost completely submerged by the

lava Lava is molten or partially molten rock (magma) that has been expelled from the interior of a terrestrial planet (such as Earth) or a Natural satellite, moon onto its surface. Lava may be erupted at a volcano or through a Fissure vent, fractu ...

flows of the surrounding Mare Imbrium. The southern end of the rim has been covered by the ejecta from Aristillus. Along the eastern inner wall and rim is an unusual narrow ribbon of dark material. English progressive rock band

Camel A camel (from and () from Ancient Semitic: ''gāmāl'') is an even-toed ungulate in the genus ''Camelus'' that bears distinctive fatty deposits known as "humps" on its back. Camels have long been domesticated and, as livestock, they provid ...

named the first song on their album '' Moonmadness'' after the crater. Science fiction author Travis J I Corcoran set much of his first novel, '' The Powers of the Earth'', on and under Aristillus.

Satellite craters

By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Aristillus.

Satellite craters

References

Sources

External links