edmund halley

edmund halley

(October 29, 1656 - January 14, 1742)

he is the famous astronomer and the first to calculate orbit of acomet

Edmund Halley was born in Hagerston, Middlesex, England (near London) as son of a wealthy merchant, salter and soapmaker. His birth date is somewhat uncertain because it is not known if at that time in his village the Gregorian or the Julian calendar was in use. There's also some dispute over the year.

He got educated at Oxford and studied at Oxford University, Queen's College, 1673-6. He worked with John Flamsteed, the Astronomer Royal in 1675-6 both at Oxford and Greenwich, and observed e.g. the occultation of Mars by the Moon on August 21, 1676. In November 1676, he gave up his studies without final exam, and sailed to St. Helena on the southern hemisphere, in order to compile a catalog of southern stars. The reasons for this are unknown, but it may be that he wanted to complement Flamsteed's mapping of the northern celestial hemisphere on the southern skies. Besides compiling this first catalog of the southern skies, Halley observed the Mercury transit of November 7, 1677. After returning to England in 1678, he got his "Catalog of the Southern Stars" published (Halley 1679). On his return, Halley was elected to the Royal Society on November 30, 1678, and King Charles II graduated him by mandate in 1679. That year, he was sent to Danzig to visit Hevelius. In the years following, he travelled Europe, urged Isaac Newton to work out and publish his Principia, and acquired the expressed enemyship of John Flamsteed. In 1691 Flamsteed succeeded in preventing his appointment as professor in Oxford. In 1704 he was eventually appointed Savilian professor of geometry at Oxford, well to the dismay of Flamsteed. Halley had observed a number of comets and, following 1695, undertook deep studies to calculate their orbits. In 1705, he published his "Astronomiae Cometiae Synopsis", including his observation that the comet he had observed in 1682 had an orbit almost identical to those of the comets of 1531 and 1607, and concluded these were apparitions of one and the same comet, the return of which he predicted for 1758. In 1710, Halley discovered the proper motion of some "fixed" stars when using Ptolemy's catalog. In 1712, he arranged to publish Flamsteed's observations and star catalogs, an endeavor he had worked on for a long time, heavily opposed by Flamsteed - who later (in 1715) arranged to burn all remaining copies he could get, about 300 of the total edition of 400. In 1715, Halley published a summary of the variable ("New") stars known at that time, six in number (Halley 1715), and in 1716, a summary on the known "nebulae", also six (Halley 1716). When Flamsteed died, his favorite enemy Halley succeeded him in 1720, then at age 64, and held this position for 21 years. Halley passed away on January 14, 1742 in Greenwich, England at age 87. The astronomical community has honored Halley by naming each one crater on Moon (8.0S, 5.7E, 36.0 km diameter, named in 1935) and Mars (48.7S, 59.3W, 84.5 km, in 1973) after him. Asteroid No. 2688 was named Halley, on its discovery by E. Bowell at Anderson Mesa on April 25, 1982; previously it had been cataloged as 1982 HG1 and former pre-discovery sightings as 1955 QN1 = 1978 SH6 = 1978 TE9 = 1978 UO. But certainly he is best remembered for the comet which he first predicted to return, the most famous of all comets, Comet 1P/Halley. Halley originally discovered two deepsky objects, globular clusters Omega Centauri (NGC 5139) and the Hercules Cluster, M13. His "Catalog of Southern Stars" (Halley 1679) includes 3 nebulous objects, and he wrote one of the first papers on nebulae, including a catalog of 6 entries/objects (Halley 1716).