Galilaei 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 ...

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 crater ...

located in the western

Oceanus Procellarum Oceanus Procellarum ( la, Ōceanus procellārum, lit=Ocean of Storms) is a vast lunar mare on the western edge of the near side of the Moon. It is the only one of the lunar maria to be called an "Oceanus" (ocean), due to its size: Oceanus Proc ...

. Some distance to the southeast is the crater Reiner, while to the south-southwest is Cavalerius. Northeast of the crater is a meandering

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 wi ...

named the Rima Galilaei. To the southeast is the unusual Reiner Gamma formation, a swirling arrangement of light-hued ray-like material. Galilaei is relatively undistinguished, with a sharp-edged rim that has a higher

albedo Albedo (; ) is the measure of the diffuse reflection of solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body that refl ...

than the surrounding maria. The inner walls slope down to a ring of debris on the outer edges of the interior floor. There is a small central rise near the midpoint. About 40 kilometers to the south is the landing site of the

Luna 9 Luna 9 (Луна-9), internal designation Ye-6 No.13, was an uncrewed space mission of the Soviet Union's Luna programme. On 3 February 1966, the Luna 9 spacecraft became the first spacecraft to achieve a survivable landing on a celestial body ...

robotic probe, the first such vehicle to make a controlled landing on the lunar surface. Despite being the first person to publish astronomical observations of the Moon with a

telescope A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observ ...

Galileo Galilei Galileo di Vincenzo Bonaiuti de' Galilei (15 February 1564 – 8 January 1642) was an Italian astronomer, physicist and engineer, sometimes described as a polymath. Commonly referred to as Galileo, his name was pronounced (, ). He wa ...

is honored only with this unremarkable formation. Initially, the name Galilaeus had been applied by

Giovanni Battista Riccioli Giovanni Battista Riccioli, SJ (17 April 1598 – 25 June 1671) was an Italian astronomer and a Catholic priest in the Jesuit order. He is known, among other things, for his experiments with pendulums and with falling bodies, for his discussion ...

, an

Italian Italian(s) may refer to: * Anything of, from, or related to the people of Italy over the centuries ** Italians, an ethnic group or simply a citizen of the Italian Republic or Italian Kingdom ** Italian language, a Romance language *** Regional Ita ...

Jesuit who produced one of the first detailed maps of the Moon in 1651, to a large and bright nearby albedo feature (now known as Reiner Gamma). The name was transferred to its present location by

Johann Heinrich Mädler Johann, typically a male given name, is the German form of ''Iohannes'', which is the Latin form of the Greek name ''Iōánnēs'' (), itself derived from Hebrew name ''Yochanan'' () in turn from its extended form (), meaning "Yahweh is Gracious" ...

in his influential Mappa Selenographica, published in collaboration with

Wilhelm Beer Wilhelm Wolff Beer (4 January 1797 – 27 March 1850) was a banker and astronomer from Berlin, Prussia, and the brother of Giacomo Meyerbeer. Astronomy Beer's fame derives from his hobby, astronomy. He built a private observatory with a ...

in four parts between 1834 and 1836. Mädler's motive for this change was the fact that his lunar map did not name albedo features, forcing him to transfer Galileo's name to an insignificant nearby crater.

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 Galilaei.

References

* * * * * * * * * * * * {{refend Impact craters on the Moon