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Robert Phillip Sharp

Expert on the geological surfaces of the Earth and the planet Mars

Robert P(hillip) Sharp (24 June 1911 – 25 May 2004) was an expert on  the geological  surfaces of the Earth and the planet Mars.  Sharp was  the former head of the geological sciences division at Caltech  from 1952 to 1968. He retired in 1979 but continued leading geological field  trips afterwards.
 
Sharp was a native of Oxnard, California; attended Caltech as an  undergraduate in 1930, earning a bachelor’s  degree (1934) and master’s degree (1935); and later, attended Harvard University for a doctorate (1938) in geology.Sharp served in the  Army Air Force during World War II as an analyst in the Artic, Desert and Tropical Information Center and achieved the rank of captain. Sharp was a professor at the University of Illinois, the University  of Minnesota and later, in 1947, at Caltech.

On 28 March 2012, NASA  named a mountain on the planet  Mars in his honor. Mount Sharp is located in the center of Gale Crater and is the expected destination of a Mars  Rover, the Mars Science Laboratory (MSL), named “Curiosity,”  planned to land in Gale Crater on 6 August 2012  Click on image below to view Mars Rover Site Landing  Accuracy on Mars: A Historical Perspective This image illustrates how spacecraft landings on Mars have become more and more
precise over the years. Since NASA’s first Mars landing of Viking in 1976, the targeted landing regions, or ellipses, have shrunk. Improvements in interplanetary navigation tightened the ellipses between the 1997 and 2008
landings of NASA’s Pathfinder and Phoenix.

NASA’s Curiosity used those improvements, in addition to hypersonic guided entry similar to that used by astronauts returning to Earth during NASA’s Apollo program, to further reduce the ellipse size and land just north of the slopes of Mount  Sharp. The area of Curiosity’s landing ellipse was just seven percent the size of the previous best landing ellipse for Phoenix. This guided entry technique also allowed a much heavier rover to land on Mars.The background
picture is from the European Space Agency’s Mars Express overlaid with topographical data from NASA’s Mars Global Surveyor.

Colorized shaded relief map of Gale Crater, based on High Resolution Stereo  Camera data.
Mount Sharp rises from the center of the crater.

The  landing ellipse for MSL is shown on the northwestern crater floor. Location Gale Crater Coordinates 5.4°S 137.8°ECoordinates: 5.4°S 137.8°E Peak Mount Sharp – 5.5 km (18,000 ft) high[1]  Discoverer NASA in the 1970s[3] Eponym Robert P. Sharp  (1911-2004)

PASADENA, Calif.
Robert Phillip Sharp, a leading authority on the surfaces of Earth and Mars and longtime head of the geological sciences division at the California Institute of Technology, died May 25 at his home in Santa Barbara. He was 92.
     Though Sharp was a renowned geologist in his own right, his most significant role was arguably his modernization of the earth sciences at Caltech during a time of unparalleled progress in the furtherance of knowledge of both our own world and of others. Sharp brought to the job a remarkable talent for hiring top people, as well as a strong interest in creating new interdisciplinary approaches to take advantage of the dawning age of manned and unmanned planetary
exploration.
    Particularly noteworthy in Sharp’s revamping of the Caltech earth sciences was his support of planetary science as a vehicle for extending geological research to the other planets, notably Mars, and for his contributions to the creation of the field of geochemistry. The latter discipline was especially important in the interpretation of lunar samples that began at Caltech in 1970. Sharp was also closely involved with NASA during the 1960s as an interpreter of the Mariner
imagery from Mars.
     In an anecdote reported by the Pasadena Star-News during Caltech’s centennial celebration in 1991, Sharp recalled how one of the Mariner technicians had told him the imagery just returned from Mars had revealed the presence of a lake. Telling the technician that a lake on Mars was absurd, he looked at the imagery and saw that the rippling features the technician had seen were actually sand dunes. “That was the beauty of it for me,” Sharp said. “Astrophysicists,
engineers, and computer guys, and they need this dumb ol’, dirty fingernail geologist like me!”
     In 1989, Sharp’s own research won him America’s highest scientific honor, the National Medal of Science, for having “illuminated the nature and origin of the forms and formation processes of planetary surfaces, and for teaching two
generations of scientists and laymen to appreciate them.” Sharp was also cited by the White House for having built the multidisciplinary Division of Geological and Planetary Sciences at Caltech.
     His many research activities included investigations of basin range structure, continental basin deposits, mountain glaciation, continental glaciation, glacial-lake shorelines, frozen ground, erosion surfaces, desert sand dunes,
glaciers, oxygen and hydrogen isotopes in snow and glacier ice, and surface forms and processes on Mars.
     His many awards and honors included his being named in 1950 by Life magazine as one of 10 outstanding U.S. college teachers; receiving the Kirk Bryan Award from the Geological Society of America in 1964; and receiving the NASA Exceptional Scientific Achievement Award Medal in 1971; election to the National Academy of Sciences in 1973; and receiving the Penrose Award from the Geological Society of America in 1977 (the society’s top honor) and the Charles P. Daly Medal from the American Geographical Society in 1991. In addition, he was honored by the Boy
Scouts of America in 1978 with the Distinguished Eagle Scout Award, and by Caltech by the institution of the Robert P. Sharp Professorship in Geology that same year.
     A native of Oxnard, California, Sharp first came to Caltech as an undergraduate in 1930, where he was a star quarterback in the days when the institute was still a competitive force in Southern California football. Sharp was one of 25 former gridiron stars who had gone on to significant careers, who were profiled in the Christmas 1958 issue of the magazine Sports Illustrated. At the time “one of the ablest, most popular teachers at Caltech,” the 165-pound Sharp lamented having been sacked so many times toward the end of his college days due to temporary 1933 changes in college rules that weighted the game “in favor of brute force.” He said of football that it served to show a scientist he needed “to be determined as hell and that there is a certain poise and aggressiveness that is desirable.”
     After earning his BS and MS at Caltech, in 1934 and 1935, respectively, Sharp went on to Harvard University for a doctorate in geology in 1938. He spent the years from 1938 to 1943 in the geology department at the University of Illinois, and then served in the U.S. Army Air Forces from 1943 to 1945, working in the Arctic, Desert, and Tropic Information Center and reaching the rank of captain. After returning from the war, he served from 1945 to 1947 on the University of Minnesota faculty, and then returned to Caltech as a professor. He was division chairman from 1952 to 1968, and retired in 1979.
     Though officially designated emeritus after his retirement, he nevertheless remained quite active, and was especially renowned in the Caltech community for his frequent field trips to numerous remote locales of geological interest. He not
only continued to be involved with educational field trips for students in the geological sciences, but also participated in field trips for Caltech alumni, Associates, Caltech staff members, and others.
     He was preceded in death by his wife, Jean Todd Sharp. His survivors include two adopted children, Kristin and Bruce.
Written by Robert Tindol Caltech Media Relations