Edmond Halley (name also spelled Edmund; born November 8, 1656 in Haggerston, Shoreditch near London, died January 14, 1742 in Greenwich) - English astronomer and mathematician. He discovered the proprietary motions of stars and the existence of elliptical cometary orbits, predicting the return of the comet known today as Halley's comet.
Son of Edmond Halley, a wealthy soap maker. In 1673, at the age of 17, Edmond Halley entered Queen's College, Oxford. Until 1678 he observed the skies above the southern hemisphere from Saint Helena, creating a register of 372 stars. Then he returned to England. Until then, he had not yet received his university diploma. Eventually, at the request of King Charles II, he received it without the final examination.
In May 1679 he was sent to Gdańsk by Robert Hooke to verify the calculations of the position of stars, questioned by members of the Royal Society, made without optical instruments by Jan Hevelius, also a member of the Society. Until July, together with the Gdańsk astronomer, he verified the calculations using his instruments, including quadrant with telescopes. The verification was successful.
An interest in the problems of gravity and Kepler's laws of planetary motion prompted him to visit Isaac Newton in August 1684, who presented him with his unpublished works clarifying the doubts. Halley persuaded Newton to write Philosophiae Naturalis Principia Mathematica (1687) and financed its printing.
In 1693, on the basis of lists of births and deaths prepared by the Wroclaw pastor Caspar Neumann, he developed a model for calculating pension contributions for the emerging insurance funds. In his analysis, he treated Wrocław as a model city - not a port (visited by a larger number of foreigners) and situated in a quiet area of the continent. According to his calculations, at the end of the 17th century, the town was to have approx. 34 thousand. residents, including men of recruiting age, between 18 and 56 years old, 9027. Child mortality was 45% between 1 and 6 years of age. On the basis of his analyzes, he also formulated conclusions for the rulers, suggesting discouragement from unmarriage both by high taxes and the compulsion of military service, and calling on the authorities to support families with many children, i.e. families with more than two children. In turn, help for the poor would consist in creating jobs so that the poor had a chance to earn a living on their own. The method of calculating premiums depending on age in some insurance companies proposed by Halley survived until the end of the 18th century.
In 1693 he used mercury as a thermometric liquid in a thermometer. In 1720 he became the Royal Astronomer.
His contribution to the science of that time was enormous. As Bill Bryson writes in his book ("A Brief History of Almost Everything"): "Edmond Halley (...) during his (...) career was a ship captain, cartographer, professor of geometry at the University of Oxford, (... ), court astronomer, inventor of the seagoing diving bell. He has written authoritative texts on magnetism, sea currents and planetary movements, as well as the effects of opium use. He developed the concept of a weather map, (...) proposed a method of measuring the Earth and its distance from the sun (...) ”.
To honor his achievements and contributions to astronomy, he is named after a crater on the moon, a crater on Mars, and a comet (which he did not discover, but was the first to suggest that the comet observed in 1682 was the same body previously seen in 1456. , 1531 and 1607).
Hollow Earth theory
John J. O'Connor; Edmund F. Robertson: Edmond Halley in MacTutor History of Mathematics archive
Halley, Edmond (Eng.)