Edmond Halley (1656-1742)
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Edmond Halley (1656-1742) was an English astronomer, geophysicist, mathematician, meteorologist, and physicist. He is best known for calculating the orbit of a comet that was later named after him and for his contributions to the development of the field of geophysics.
Halley was born in Haggerston, London, England, in 1656. He was the second son of a wealthy soapmaker, and he attended St. Paul's School in London before entering Queen's College, Oxford, at the age of 18. While at Oxford, he became interested in mathematics and astronomy and began to study under the guidance of the astronomer John Flamsteed.
After leaving Oxford in 1676, Halley traveled to the island of Saint Helena in the South Atlantic Ocean to map the stars of the southern hemisphere. He returned to England in 1678 and became a Fellow of the Royal Society, where he published several papers on astronomy and magnetism.
In 1684, Halley traveled to the continent to meet with the great astronomer Johannes Hevelius in Poland and the physicist Christiaan Huygens in Paris. During this trip, he became interested in the study of comets and began to collect data on their orbits.
In 1686, Halley published his first paper on the subject of comets, in which he described the three comets that had appeared in the sky in the years 1531, 1607, and 1682. He suggested that these comets were one and the same and that they would return again in 1758.
Halley's prediction was proven correct when the comet reappeared in 1758, a few years after his death. The comet was named Halley's Comet in his honor.
In addition to his work on comets, Halley also made significant contributions to the field of geophysics. In 1693, he published a paper on the magnetic field of the Earth, in which he suggested that the variations in the magnetic field were caused by the motion of the Earth's molten core. He also proposed that the aurora borealis, or northern lights, were caused by the interaction of charged particles from the Sun with the Earth's magnetic field.
Halley was also the first person to map the variation of the Earth's magnetic field, a project that he worked on with the help of his friend, the surveyor William Whiston. He also invented the diving bell, a device that allowed divers to remain underwater for extended periods of time.
Halley died in Greenwich, London, on January 14, 1742, at the age of 85. He is remembered as one of the greatest astronomers of the 17th and 18th centuries, and his contributions to the field of geophysics paved the way for further research in the area.
