Erlanger is a very deep lunar

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 ...

that lies near the

north pole The North Pole, also known as the Geographic North Pole or Terrestrial North Pole, is the point in the Northern Hemisphere where the Earth's rotation, Earth's axis of rotation meets its surface. It is called the True North Pole to distingu ...

of the

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...

. Due to its position near the

lunar north pole The lunar north pole is the point in the Northern Hemisphere of the Moon where the lunar axis of rotation meets its surface. The lunar North Pole is the northernmost point on the Moon, lying diametrically opposite the lunar south pole. It define ...

(and given that the Moon's axis is only tilted about 1.5°), sunlight only rarely falls on the bottom, and the 2008

Chandrayaan-1 Chandrayaan-1 (, ) was the first Indian lunar probe under the Chandrayaan program. It was launched by the Indian Space Research Organisation in October 2008, and operated until August 2009. The mission included a lunar orbiter and an impact ...

probe hoped to find that

ice Ice is water frozen into a solid state, typically forming at or below temperatures of 0 degrees Celsius or Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaqu ...

from

comet A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena ...

impacts had accumulated there. Erlanger is one of the Moon's

permanently shadowed crater A permanently shadowed crater is a depression on a body in the Solar System within which lies a point that is always in darkness. As of 2019, there are 324 known permanently shadowed regions on the Moon. Such regions also exist on Mercury and ...

s. The crater was named by the International Astronometrical Union on January 22, 2009, after the American physiologist and 1944

Nobel Prize The Nobel Prizes ( ; sv, Nobelpriset ; no, Nobelprisen ) are five separate prizes that, according to Alfred Nobel's will of 1895, are awarded to "those who, during the preceding year, have conferred the greatest benefit to humankind." Alfr ...

winner Joseph Erlanger.

References

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External links

Article about Erlanger by Dr. Phil Plait

USGS Gazetteer of Planetary Nomenclature entry for Erlanger

{{Craters on the Moon: C-F Impact craters on the Moon