John Edward Geake (22 April 1925 – 3 June 1998) was a Britishastronomer, noted as alunar scientist and scientific instrument designer.^[1][2]

John Edward Geake was born on 22 April 1925 inManchester, England.^[3] His postgraduate studies at theUniversity of Manchester Institute of Science and Technology (UMIST) related to the study of astronomical spectra using aphotoelectricphotometer. His work parallelled that ofW. Albert Hiltner's team in the United States; although at the time neither knew of the other's work, and their methods were different. This research, which was long before the days of space exploration, led to laboratory measurement ofluminescence frommeteorite samples, which could be compared with lunar luminescence in an attempt to determine the composition of thelunar surface. His expertise was recognised by both theAmerican and theSoviet space agencies, both of whom allocated to him lunar samples for study.^[1]

He was aNASA principal investigator, and an editor ofLunar Science Conference Proceedings. One of his focuses was in trying to gain information from thepolarization of light scattered from the surfaces of solid bodies in theSolar System. This involved comparison of laboratory measurements on samples of known characteristics against astronomical observations. This led to analysis of data collected by thePioneer 10 andPioneer 11 spacecraft, targeted atJupiter andSaturn.^[1] He became well known for this work,^[2] which was continued after his death byTom Gehrels of theUniversity of Arizona; where Geake had held the post ofadjunct professor.^[1] Geake was also a fellow at theRoyal Astronomical Society,^[4] and a member of theInternational Astronomical Union.^[5]

Geake invented the first linear direct-readingrefractometer for liquids, which has since been used in many practical applications.^[2] He designed the "UMIST Refractometer" subsystem for theCassini–Huygens probe, which reached Saturn's moonTitan after his death in 2004. He also invented a spectral differentiating refractometer.^[2][6][7]

Geake died on 3 June 1998 after retiring in 1992 with the title ofreader. He had worked in UMIST physics department for 35 years, where he made major contributions including the founding of the Industrial Science Group, one of the earliest university-industry liaison groups.^[1]

In his private life, Geake was a devout member of Fourth Church of Christ, Scientist, Manchester, and a visiting chaplain atStrangeways Prison.^[1][8] He had two daughters with his wife, Mary.^[1] The archaeologistHelen Geake is his cousin.^{[citation needed]}

Themain-belt asteroid9298 Geake, discovered byEdward Bowell atAnderson Mesa Station in 1985, was named in his honour.^[2]

• BAA Meeting at Manchester Metropolitan University April 1996
• Obituary by Michael Woolfson
• Reflectance polarimetry of Callisto and the evolution of the Galilean, Jean-ClaudeMandeville, John E.Geake and Audouin Dollfus (1978)
• The Cassini-Huygens Mission – Acknowledgements, Google books (2013)

• 1925 births
• 1998 deaths
• Scientists from Manchester
• Engineers from Manchester
• 20th-century British astronomers
• 20th-century British cartographers
• 19th-century British inventors
• Selenographers
• British Christian Scientists
• NASA people
• Fellows of the Royal Astronomical Society
• Alumni of the University of Manchester Institute of Science and Technology
• Academics of the University of Manchester Institute of Science and Technology

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