Hyginus is a

lunar Lunar most commonly means "of or relating to the Moon". Lunar may also refer to: Arts and entertainment * ''Lunar'' (series), a series of video games * "Lunar" (song), by David Guetta * "Lunar", a song by Priestess from the 2009 album ''Prior t ...

caldera A caldera ( ) is a large cauldron-like hollow that forms shortly after the emptying of a magma chamber in a volcano eruption. When large volumes of magma are erupted over a short time, structural support for the rock above the magma chamber is ...

located at the east end of the

Sinus Medii Sinus Medii (Latin ''sinus mediī'' "Middle Bay") is a small lunar mare. It takes its name from its location at the intersection of the Moon's equator and prime meridian; as seen from the Earth, this feature is located in the central part of the ...

. It was named after ancient Roman astronomer

Gaius Julius Hyginus Gaius Julius Hyginus (; 64 BC – AD 17) was a Latin author, a pupil of the scholar Alexander Polyhistor, and a freedman of Caesar Augustus. He was elected superintendent of the Palatine library by Augustus according to Suetonius' ''De Grammatic ...

. Its rim is split by a 220 kilometer-long

rille Rille (German for 'groove') is typically used to describe any of the long, narrow depressions in the surface of the Moon that resemble channels. The Latin term is ''rima'', plural ''rimae''. Typically, a rille can be several kilometers wid ...

, Rima Hyginus, that branches to the northwest and to the east-southeast. The crater is deeper than the rille, and lies at intersection of the rille's branches. Together, the crater and the rille form a prominent feature in an otherwise flat surface. Smaller craters along the length of the rille may have been caused by the collapse of an underlying structure. Hyginus is one of the few craters on the Moon that was not created as a result of an impact, and is instead believed to be

volcanic A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. On Earth, volcanoes are most often found where tectonic plates a ...

in origin. It lacks the raised outer rim that is typical with

impact crater An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, impact craters ...

s. Hyginus was considered a possible landing site during the Apollo Program, because it was thought to be a site of potentially active volcanism. The landing point would have been northwest of the crater, within a few kilometers of the main crater rim and the rille to the west. Major objectives would have included examining and sampling the Cayley Formation and dark overlying rocks, the crater rim and floor, and other possible volcanic features in the area. It was near Hyginus that in 1878 Hermann Klein claimed to have discovered a new crater.

Views

File:Rima Hyginus 3073 med.jpg,

Lunar Orbiter 3 The Lunar Orbiter 3 was a spacecraft launched by NASA in 1967 as part of the Lunar Orbiter Program. It was designed primarily to photograph areas of the lunar surface for confirmation of safe landing sites for the Surveyor and Apollo missions. ...

image File:Hyginus and Rima Hyginus (LRO).png, LRO image of Hyginus (lower right) and part of Rima Hyginus File:AS10-31-4650 Rima Hyginus.jpg, Oblique view from

Apollo 10 Apollo 10 (May 18–26, 1969) was a human spaceflight, the fourth crewed mission in the United States Apollo program, and the second (after Apollo8) to orbit the Moon. NASA described it as a "dress rehearsal" for the first Moon landing, and ...

File:Rima Hyginus AS17-M-1674.jpg, Oblique view from

Apollo 17 Apollo 17 (December 7–19, 1972) was the final mission of NASA's Apollo program, the most recent time humans have set foot on the Moon or traveled beyond low Earth orbit. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt walked on ...

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 Hyginus.

References

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External links

Hyginus at The Moon Wiki
* * * {{cite web, last = Wood , first = Chuck , date = March 20, 2010 , url = http://lpod.wikispaces.com/March+20%2C+2010 , title = Another Ina? , publisher = Lunar Photo of the Day Geological features on the Moon