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Edmond Halley

2007 Schools Wikipedia Selection. Related subjects: Mathematicians; Space
(Astronomy)

   Portrait of Edmond Halley painted around 1687 by Thomas Murray (Royal
   Society, London)
   Portrait of Edmond Halley painted around 1687 by Thomas Murray ( Royal
   Society, London)
   Portrait of Edmond Halley
   Portrait of Edmond Halley
   Bust of Edmond Halley in the Museum of the Royal Greenwich Observatory
   Bust of Edmond Halley in the Museum of the Royal Greenwich Observatory

   Edmond Halley FRS (sometimes "Edmund", November 8, 1656 – January 14,
   1742) was an English astronomer, geophysicist, mathematician,
   meteorologist, and physicist.

Biography and career

   Halley was born at Haggerston, London, the son of a wealthy soapboiler.
   As a child, he was very interested in mathematics. He studied at St
   Paul's School, and then from 1673 at The Queen's College, Oxford.
   Whilst an undergraduate he published papers on the solar system and
   sunspots.

   On leaving Oxford, in 1676, he visited the south Atlantic island of St.
   Helena with the intention of studying stars from the Southern
   Hemisphere. He returned to England in November 1678. In the following
   year he published Catalogus Stellarum Australium which included details
   of 341 southern stars. These additions to the star map earned him
   comparison with Tycho Brahe. He was awarded his M.A. degree at Oxford
   and elected as a Fellow of the Royal Society.

   In 1686 Halley published the second part of his expedition, being 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.

   Halley married in 1682 and settled in Islington. 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 Isaac Newton, only to find that Newton had solved
   the problem but published nothing. Halley convinced him to write the
   Principia Mathematica Philosophiae Naturalis ( 1687), which was
   published at Halley's expense.

   In 1690, Halley built a diving bell, in which device 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 one and a half
   hours. Halley's bell was of little use for practical salvage work, as
   it was very heavy, but he did make improvements to his bell over time,
   later extending his underwater exposure time to over 4 hours.

   In 1693 he published an article on life annuities, which featured an
   analysis of age-at-death taken from the records of Breslau, a
   Polish-German town known for keeping meticulous records. This 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 he received a commission as captain of HMS Paramore to make
   extensive observations on the conditions of terrestrial magnetism. This
   task he accomplished in an Atlantic voyage which lasted two years, and
   extended from 52 degrees north to 52 degrees south. The results were
   published in a 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 he was appointed Savilian professor of geometry at
   Oxford University, 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. When it did it became
   generally known as Halley's Comet.

   In 1716 Halley 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. It is not to Halley's credit
   that he failed to acknowledge Gregory's priority in this matter. In
   1718 he discovered the proper motion of the "fixed" stars by comparing
   his astrometric measurements with those of the Greeks.

   In 1720, Halley succeeded John Flamsteed as Astronomer Royal, a
   position which he held until his death. He was buried at St. Margaret's
   Church in Lee in south-east London.

Hollow Earth

   In 1692 (Philosophical Transactions of Royal Society of London), Halley
   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.
   Atmospheres separate these shells, and each shell has its own magnetic
   poles. The spheres rotate at different speeds. Halley proposed this
   scheme in order to explain anomalous compass readings. He envisaged the
   atmosphere inside as luminous (and possibly inhabited) and speculated
   that escaping gas caused the Aurora Borealis.

Named after Halley

   Plaque in South Cloister of Westminster Abbey
   Plaque in South Cloister of Westminster Abbey
     * Halley's Comet — Halley predicted the comet's return.
     * Halley crater on Mars
     * Halley crater on the Moon
     * Halley Research Station, Antarctica

   An alternative (and incorrect) pronunciation of Halley's surname, to
   rhyme with "Bailey", has led to rock and roll singer Bill Haley
   punningly calling his backing band "His Comets" after Halley's Comet.
    Preceded by
   John Flamsteed Astronomer Royal
                  1720–1742       Succeeded by
                                  James Bradley
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