Edmond Halley FRS born this day in 1656

English astronomer, geophysicist, mathematician, meteorologist, and physicist Edmond Halley FRS was born on 8 November 1656 he is best known for computing the orbit of the eponymous Halley’s Comet. He was also the second Astronomer Royal in Britain, following in the footsteps of John Flamsteed.

Halley was born in Haggerston, Shoreditch, England. His father, Edmond Halley Sr., came from a Derbyshire family and was a wealthy soap-maker in London. As a child, Halley was very interested in mathematics. He studied at St Paul’s School, and then, from 1673, at The Queen’s College, Oxford. While an undergraduate, Halley published papers on the Solar System and sunspots.
 
Upon leaving Oxford, in 1676, Halley visited the south Atlantic island of Saint Helena and set up an observatory with a 24-foot-long (7.3 m) aerial telescope with the intention of studying stars from the Southern Hemisphere. Then In November 1678 He returned to England and In the following year he went to Danzig (Gdansk) on behalf of the Royal Society to help resolve a dispute which had arisen because an astronomer named Johannes Hevelius had made observations without the use of a telescope, and his results had been called into oquestion by a fellow astronomer named Robert Hooke, so Halley was requested to stay with Hevelius, in order to observe and verified the quality of his observations.

In That same year, Halley also published the Catalogus Stellarum Australium which included details of 341 southern stars, and these additions to present-day star maps earned him comparison with Tycho Brahe. Halley was subsequently awarded an M.A. degree at Oxford and elected as a Fellow of the Royal Society.

In 1686 Halley published the second part of the results from his Helenian expedition, whichwere a paper and chart on trade winds and monsoons. In this he identified solar heating as the cause of atmospheric motions. He also established the relationship between barometric pressure and height above sea level. His charts were an important contribution to the emerging field of information visualization.
 
In 1682 Halley married Mary Tooke and they settled in Islington.where They had three children. He spent most of his time on lunar observations, but was also interested in the problems of gravity. One problem that attracted his attention was the proof of Kepler’s laws of planetary motion. In August 1684 he went to Cambridge to discuss this with Sir Isaac Newton, only to find that Newton had solved the problem, but published nothing. Halley convinced him to write the Philosophiæ Naturalis Principia Mathematica (1687), which was published at Halley’s expense.
 
In 1691, Halley built a diving bell, in which the atmosphere was replenished by way of weighted barrels of air sent down from the surface. In a demonstration, Halley and five companions dived to 60 feet in the River Thames, and remained there for over an hour and a half. Unfirtunately Halley’s bell was of little use for practical salvage work, because it was too heavy, However he made improvements to it over time, and was later able to extend his underwater exposure time to over 4 hours, unfortunately as a result of this  Halley suffered one of the earliest recorded cases of middle ear barotrauma.

Then in That same year, at a meeting of the Royal Society, Halley introduced a rudimentary working model of a magnetic compass using a liquid-filled housing to damp the swing and wobble of the magnetized needle. In 1691 Halley sought the post of Savilian Professor of Astronomy at Oxford, but, due to his well-known atheism, was opposed by the Archbishop ofCanterbury, John Tillotson and Bishop Stillingfleet. The post went instead to David Gregory, who had the support of Isaac Newton

Not to be discouraged, Halley then put forth the idea of a hollow Earth consisting of a shell about 500 miles (800 km) thick, two inner concentric shells and an innermost core, about the diameters of the planets Venus, Mars, and Mercury. He suggested that atmospheres separated these shells, and that each shell had its own magnetic poles, with each sphere rotating at a different speed. Halley proposed this scheme in order to explain anomalous compass readings. He envisaged each inner region as having an atmosphere and being luminous (and possibly inhabited), and speculated that escaping gas caused the Aurora Borealis.

In 1693 Halley published an article on life annuities, which featured an analysis of age- at-death on the basis of the Breslau statistics Caspar Neumann had been able to provide. This article allowed the British government to sell life annuities at an appropriate price based on the age of the purchaser. Halley’s work strongly influenced the development of actuarial science. The construction of the life-table for Breslau, which followed more primitive work by John Graunt, is now seen as a major event in the history of demography.

In 1698, Halley was given the command of the Paramour, a 52-foot ship, so that he could carry out investigations in the South Atlantic into the laws governing the variation of the compass. On 19 August 1698, he took command of the ship and, in November 1698, sailed on what was the first purely scientific voyage by an English naval vessel. The Paramour returned to England in July 1699. where Halley  received a commission as a temporary Captain in the Royal Navy, recommissioned the Paramour on 24 August 1699 and sailed again in September 1699 to make extensive observations on the conditions of terrestrial magnetism. This task he accomplished in a second Atlantic voyage which lasted until 6 September 1700, and extended from 52 degrees north to 52 degrees south. The results were published in General Chart of the Variation of the Compass (1701). This was the first such chart to be published and the first on which isogonic, or Halleyan, lines appeared.

In November 1703 Halley was appointed Savilian Professor of Geometry at the University of Oxford, his theological enemies, John Tillotson and Bishop Stillingfleet having died, and received an honorary degree of doctor of laws in 1710. In 1705, applying historical astronomy methods, he published Synopsis Astronomia Cometicae, which stated his belief that the comet sightings of 1456, 1531, 1607, and 1682 related to the same comet, which he predicted would return in 1758. Halley did not live to witness the comet’s return, but when it did, the comet became generally known as Halley’s Comet.

In 1716 Halley also suggested a high-precision measurement of the distance between the Earth and the Sun by timing the transit of Venus. In doing so he was following the method described by James Gregory in Optica Promota (in which the design of the Gregorian telescope is also described). It is reasonable to assume Halley possessed and had read this book given that the Gregorian design was the principal telescope design used in astronomy in Halley’s day. Then In 1718 he discovered the proper motion of the “fixed” stars by comparing his astrometric measurements with those given in Ptolemy’s Almagest. Arcturus and Sirius were two noted to have moved significantly, the latter having progressed 30 arc minutes (about the diameter of the moon) southwards in 1800 years.
 
In 1720, together with his friend the antiquarian William Stukeley, Halley participated in the first attempt to scientifically date Stonehenge. Assuming that the monument had been laid out using a magnetic compass, Stukeley and Halley attempted to calculate the perceived deviation introducing corrections from existing magnetic records, and suggested three dates (AD 920, AD 220 and 460 BC), the earliest being the one accepted. These dates were wrong by thousands of years, but the idea that scientific methods could be used to date ancient monuments was revolutionary in its day.

In 1720 Halley eventually succeeded John Flamsteed  as Astronomer Royal, a position he held until his death on the 14th January 1742 at the age of 85. Halley was buried in the graveyard of the old church of St. Margaret,  at Lee, South London . In the same vaultis Astronomer Royal John Pond and the unmarked grave of Astronomer Royal Nathaniel Bliss is also nearby.