Pallas is a heavily eroded

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 craters ...

located to the north 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 the German-born Russian natural historian

Peter Simon Pallas Peter Simon Pallas Fellow of the Royal Society, FRS FRSE (22 September 1741 – 8 September 1811) was a Prussian zoologist and botanist who worked in Russia between 1767 and 1810. Life and work Peter Simon Pallas was born in Berlin, the son ...

. To the northwest is the smaller but less worn crater Bode. Pallas shares a low wall with the crater Murchison that is attached to the southeast, and there are two gaps in the shared rim. The outer wall of Pallas is worn, notched, and somewhat distorted in shape. The associated crater Pallas A lies across the northwest rim. The inner floor of Pallas has been flooded by

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 moon onto its surface. Lava may be erupted at a volcano or through a fracture in the crust, on land or un ...

, leaving a relatively flat surface. The crater possesses a central peak complex.

Lunar flare

On November 15, 1953, the physician and amateur

astronomer An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, natural satellite, moons, comets and galaxy, g ...

Dr. Leon H. Stuart took a picture of the Moon that appeared to show a flare of light about 16 km southeast of Pallas. The flare was estimated to last for about 8–10 seconds. The report was published in a 1956 issue of ''The Strolling Astronomer'', a newsletter. However the incident was dismissed by professionals of the period as more likely a

meteoroid A meteoroid () is a small rocky or metallic body in outer space. Meteoroids are defined as objects significantly smaller than asteroids, ranging in size from grains to objects up to a meter wide. Objects smaller than this are classified as micr ...

entering the Earth's

atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...

. Many years later Dr.

Bonnie Buratti Bonnie J. Buratti (born 1952) is an American planetary scientist in the Division of Earth and Space Sciences at the Jet Propulsion Laboratory in Pasadena, California, where she leads the Comets, Asteroids, and Satellites Group. Her research invol ...

JPL The Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, United States. Founded in the 1930s by Caltech researchers, JPL is owned by NASA an ...

saw the photograph and decided to investigate. Assisted by a graduate student, she identified a 1.5 km. diameter crater imaged by the

Clementine spacecraft ''Clementine'' (officially called the Deep Space Program Science Experiment (DSPSE)) was a joint space project between the Ballistic Missile Defense Organization (previously the Strategic Defense Initiative Organization) and NASA, launched ...

. The crater has the correct size, shape, and

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, 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 ...

to match the expected impact energy. Some astronomers now agree that Dr. Stuart may indeed have photographed an asteroid impact on the Moon.

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 Pallas.

References

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External links

Pallas at The Moon Wiki
* * - also appeared on the August 24, 2004 LPOD * * {{cite web, last = Wood , first = Chuck , date =April 8, 2010 , url = https://lpod.wikispaces.com/April+8%2C+2010 , title = Textured Ejecta , publisher = Lunar Photo of the Day - Rimae Bode, also includes Pallas crater Impact craters on the Moon