Einstein A Crater Lies as Young Crater in the Center of Einstein Crater

Summary: Einstein A Crater lies as young crater in the center of Einstein Crater, a primary crater parenting three satellites on the lunar far side.

Image shows satellite Einstein A as a mid-interior floor occupant of its parent, Einstein Crater: courtesy NASA / Goddard, via NASA

Einstein A Crater lies as a young crater in the center of Einstein Crater, an impact-battered lunar impact crater credited with three satellites on the lunar far side.

Satellite Einstein A is situated in the center of its parent’s interior floor. Anglo-Australian astronomer David A. Allen described Einstein A in the 1966-1967 issue of the Journal of the British Astronomical Association. He noted its position as a “. . . prominent central crater . . .” and described the primary crater’s interior satellite as a “. . . magnificent object . . .” (page 252).

The National Aeronautics and Space Administration (NASA) profiled Einstein A and Einstein Crater for the space agency’s online mission pages on the Lunar Reconnaissance Orbiter (LRO). An image feature, “Einstein and Einstein A: A Study in Crater Morphology,” posted May 14, 2010, considered the satellite and its primary crater as revelatory of “. . . the relative age and shape of an impact crater.”

NASA described Einstein as “. . . a fairly large crater that spans 198 km across.” Age cannot be determined, however, from “. . . size alone . . .”

Einstein A’s placement “. . . squarely in the middle of the floor of Einstein” indicates the satellite’s youthfulness. Also, the “. . . frequency and distribution of impact craters overprinted on its rim and floor” inform a crater’s relative age. The smaller number of impacts sustained by younger craters allows for their retention of their “original morphology.”

A comparison of the structures of Einstein A and Einstein Crater reveals Einstein A as “. . . a relatively young crater as compared to Einstein . . .” Smaller impacts over time have yielded a “somewhat degraded” reshaping of Einstein Crater’s original structure. Retention of its original structure attests to Einstein A’s relative youth with respect to its parent. Einstein A presents a raised rim and also exhibits an ejecta blanket.

David Allen’s paper in the 1966-1967 issue of the Journal of the British Astronomical Association credited English amateur astronomer Sir Patrick Moore (March 4, 1923-Dec. 9, 2012) with the first sighting of Einstein Crater and central, interior satellite Einstein A. Sir Patrick first saw Einstein and Einstein A via a 3-inch (7.5-centimeter) refractor in 1939.

The International Astronomical Union (IAU) adopted Einstein as the primary crater’s official name in 1964. Approval was granted during the organization’s XIIth (12th) General Assembly, held in Hamburg, Germany, from Tuesday, Aug. 25, to Thursday, Sept. 3. The crater is named after German American physicist Albert Einstein (March 14, 1879-April 18, 1955). The designations of Einstein A, Einstein R and Einsten S for the Einstein Crater system’s three satellites were approved in 2006.

Prior to its official naming, the crater system was known as Caramuel. In a paper published in the 1964-1965 issue of the Journal of the British Astronomical Association, Sir Patrick noted confusing misnomers involving Einstein Crater. He attributed the name of Caramuel to Welsh-born astronomer and engineer Hugh Percy Wilkins (Dec. 4, 1896-Jan. 23, 1960). Wilkins, however, intended the name for “. . . a different formation” (page 142). Wilkins’ Caramuel actually has turned out to reference satellite Simpelius D, according to David Allen’s 1966-1967 paper (page 255).

Allen noted the paucity of “professional photographs” of Einstein Crater and Einstein A. He indicated, however, that Soviet lunar probe Zond 3 obtained photographs of the area. The large convex mound that hosts Einstein A stands out as “. . . one of the brightest spots in the region” (page 252).

Launched July 18, 1965, from southern Kazakhstan’s Baikonur Cosmodrome, Zond 3 made a lunar flyby on July 20. For 68 minutes, the spacecraft took 25 “very good quality” photographs of the lunar far side from distances of 11,570 to 9,960 kilometers, according to David R. Williams’ profile of Zond 3 on NASA’s National Space Science Data Center (NSSDC) website.

The takeaways for Einstein A Crater as a young crater in the center of Einstein A are that the Einstein Crater system’s interior satellite reveals its youthfulness through retention of its original structure and its location in the middle of its parent’s interior floor; that English amateur astronomer Sir Patrick Moore is credited with Einstein Crater’s first sighting, which took place in 1939; and that photographs obtained July 1965 by Soviet lunar probe Zond 3 reveal the mound on which satellite Einstein A resides as one of the region’s brightest places.

“First Detailed View of Orientale Basin” shows Einstein Crater with interior satellite Einstein A as bullseye crater west of Oceanus Procellarum; photo obtained May 25, 1967, at 05:33:34 Greenwich Mean Time, by NASA-Boeing Lunar Orbiter IV, from altitude of 2,721 kilometers; The Boeing Company, Lunar Orbiter IV Photographic Mission Summary (1968), frontispiece: Public Domain, via NASA NTRS (NASA Technical Reports Server)

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Image shows satellite Einstein A as a mid-interior floor occupant of its parent, Einstein Crater: courtesy NASA / Goddard, via NASA @ https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lola-20100514-einstein.html

“First Detailed View of Orientale Basin” shows Einstein Crater with interior satellite Einstein A as bullseye crater west of Oceanus Procellarum; photo obtained May 25, 1967, at 05:33:34 Greenwich Mean Time, by NASA-Boeing Lunar Orbiter IV, from altitude of 2,721 kilometers; The Boeing Company, Lunar Orbiter IV Photographic Mission Summary (1968), frontispiece: Public Domain, via NASA NTRS (NASA Technical Reports Server) @ https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680017342.pdf

For further information:

Allen, D. (David) A. “The Lunar Crater Caramuel.” Journal of the British Astronomical Association, vol. 76, no. 4 (Session 1966-67): 248-255.
Available via Harvard ADSABS @ http://articles.adsabs.harvard.edu/full/seri/JBAA./0076//0000248.000.html

Allen, D. (David) A.; and C.J. Andrews. “The Last Word on Einstein (Caramuel).” Journal of the British Astronomical Association, vol. 79, no. 4 (Session 1968-1969): 288-290.
Available via Harvard ADSABS @ http://adsabs.harvard.edu/full/1969JBAA...79..288A
Available via Harvard ADSABS @ http://adsabs.harvard.edu/pdf/1969JBAA...79..288A

The Boeing Company. Lunar Orbiter IV: Photographic Mission Summary. Prepared by The Boeing Company, Seattle, Wash., for Langley Research Center. NASA Contractor Report NASA CR-1054.Washington DC: National Aeronautics and Space Administration, June 1968.
Available via NASA NTRS (NASA Technical Reports Server) @ https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19680017342.pdf

Consolmagno, Guy; and Dan M. Davis. Turn Left at Orion. Fourth edition. Cambridge UK; New York NY: Cambridge University Press, 2011.

Grego, Peter. The Moon and How to Observe It. Astronomers’ Observing Guides. London UK: Springer-Verlag, 2005.

Jenner, Lynn, page ed. “Einstein and Einstein A: A Study in Crater Morphology.” NASA > Missions > Lunar Reconnaissance Orbiter (LRO) > Multimedia. May 14, 2010.
Available @ https://www.nasa.gov/mission_pages/LRO/multimedia/lroimages/lola-20100514-einstein.html

Levy, David H. Skywatching. Revised and updated. San Francisco CA: Fog City Press, 1994.

Malin, David. “Obituary: David Allen (1946-1994).” The Observatory, vol. 114, no. 1122 (October 1994): 250-252.
Available via Harvard ADSABS @ http://adsabs.harvard.edu/full/1994Obs...114..250M
Available via Harvard ADSABS @ http://adsabs.harvard.edu/pdf/1994Obs...114..250M

Marriner, Derdriu. “Einstein Crater Honors German American Physicist Albert Einstein.” Earth and Space News. Wednesday, March 6, 2013.
Available @ https://earth-and-space-news.blogspot.com/2013/03/einstein-crater-honors-german-american.html

Marriner, Derdriu. “Einstein Crater Parents Three Satellites On Near Side’s Western Limb.” Earth and Space News. Wednesday, March 13, 2013.
Available @ https://earth-and-space-news.blogspot.com/2013/03/einstein-crater-parents-three.html

Moore, Patrick. “The Lunar Crater Caramuel.” Journal of the British Astronomical Association, vol. 75, no. 3 (Session 1964-65): 140-144.
Available via Harvard ADSABS @ http://articles.adsabs.harvard.edu/full/seri/JBAA./0075//0000142.000.html

Moore, Patrick, Sir. Philip’s Atlas of the Universe. Revised edition. London UK: Philip’s, 2005.