Gerald Maurice Clemence | |
|---|---|
| Born | (1908-08-16)August 16, 1908 |
| Died | November 22, 1974(1974-11-22) (aged 66) Providence,Rhode Island,U.S. |
| Alma mater | Brown University (PhB) |
| Awards | Gold Medal of the Royal Astronomical Society (1965) James Craig Watson Medal (1975) |
| Scientific career | |
| Fields | Astronomy,Celestial mechanics |
| Institutions | United States Naval Observatory Yale University |
Gerald Maurice Clemence (16 August 1908 – 22 November 1974) was an Americanastronomer. Inspired by the life and work ofSimon Newcomb, his career paralleled the huge advances in astronomy brought about by the advent of theelectronic computer. Clemence did much to revive the prestige of theU.S. Nautical Almanac Office.[1]
Born on a farm nearGreenville, Rhode Island, Gerald's parents were Richard R. Clemence and his wife, Lora,née Oatley. Much of his elementary education was at home with his mother, herself a schoolteacher, and he learned about astronomy from his own enthusiastic reading. Clemence attendedBrown University and readmathematics, achieving aPhB degree in 1930. In his own words, "as a recreation", he took thecivil service examination for the job description "astronomer" and finished first out of fifty candidates, winning appointment at theUnited States Naval Observatory. Taking up the post, he married Edith Melvina Vail, anurse, in 1929.[1]
After initial work in the Time Service Department, alongsideWilliam Markowitz,[2] Clemence was assigned to work underH. R. Morgan.George William Hill had computed theorbits ofJupiter andSaturn in the nineteenth century and Newcomb had completed the work for the otherplanets of theSolar System. However, there was now almost fifty years of new observational data and Clemence set to recalculate theorbital elements ofMercury to provide moreaccurate predictions. His results, published in 1943, clearly showed theperihelion precession of Mercury predicted by thegeneral theory of relativity.[1][3]
Clemence identified systematic errors in the predictions ofMars' path. Theresiduals showed a markedperiodicity and Clemence concluded that theFourier series on which the predictions were based was wrong. Clemence set out to derive a new series from scratch using the methods detailed by Hill andPeter Andreas Hansen in the nineteenth century. The calculations were carried out with "a lead pencil, large sheets of computing paper, [and] a hand-operatedMillionaire desk calculator".[1] Though electronic calculators were available towards the end of the project, the calculations took twelve years.[4]
Wallace John Eckert was appointed as director of the Nautical Almanac Office in 1940 and immediately imported his enthusiasm for usingpunched card machines for scientific calculation. Clemence was an early senior appointment to the new regime and soon saw the potential of electronic computation, using it initially on his Mars work but increasingly on the military work whose priority escalated following the entry of the U.S. intoWorld War II.[1]
Clemence was appointed assistant director in 1942 and was joined on the staff byPaul Herget.[1] The pair worked on calculatingmathematical tables and developed theoptimum-interval technique to construct tables calculated at non-constant intervals and for whichlinear interpolation was everywhere legitimate.[5]
In 1945, Eckert left for theIBM-sponsored computing laboratory atColumbia University and Herget became director of theCincinnati Observatory. Clemence was promoted to director of the Nautical Almanac Office, the post once held by his role-model Newcomb, and proved an able and energetic administrator.[1]
In 1947, there began an intense period of cooperative research oncelestial mechanics between Clemence's office, Eckert's group at Columbia andYale University Observatory, under the direction ofDirk Brouwer, a former collaborator of Eckert's on punched cards.[1]
![[icon]](/mt/?noimg=&dark=on&url=https%3a%2f%2fen.wikipedia.org%2fwiki%2fFile%3aWiki_letter_w_cropped.svg) | This sectionneeds expansion. You can help byadding to it.(June 2008) |
In 1958, Clemence was appointed first scientific director of theU.S. Naval Observatory, a post he again addressed with enthusiasm and vigour. His ownoriginal research necessarily took a lower profile but he continued to publish onrelativity,astronomical constants andtime measurement, as well as collaborating on two text books.[1][6][7][8][9]
However, Clemence's passion for research ultimately led him to relinquish his managerial roles in 1962, and, in 1963 Brouwer found him a post at Yale. Here, Clemence continued his work on theperturbation theory of theEarth's orbit but it was interrupted, never to be completed, in 1966 when Brouwer's death demanded that Clemence take over the administration of the department.[1]
He died inProvidence, Rhode Island on November 22, 1974, after an illness of several months.[1]
Clemence was reserved and dignified, conservative in manner and appearance. In writing he was concise and accurate. He was sincere and forthright with a code of ethics inherited from his parents. He was a family man, father of two sons, and always maintained contact with his three brothers and his sister. He was a keen, and self-taught,musician, accomplished atviolin,piano andorgan. He was also a keenrailfan.[1]
{{cite book}}:ISBN / Date incompatibility (help)| International | |
|---|---|
| National | |
| Academics | |
| People | |
| Other | |
