Francis Baily
Francis Baily (* April 28, 1774 in Newbury, Berkshire, † August 30 1844 in London ) was an English astronomer. He has been dealing with star catalogs for this purpose, he published numerous works. He described the phenomenon of Bailyschen pearls (English: Baily's beads or Perlschnurphänomen ) and was later president of the Royal Astronomical Society.
Life and work
Baily initially proposed a commercial career. After his training, he traveled 1796/97 are still uninhabited areas of North America. After his return, he worked from 1799 to the London Stock Exchange (LSE ). In the years 1802-1810 he authored several publications on leases, pensions and insurance companies, which gained him a high reputation and a secure income. In 1825 he retired from the finance, in order to devote himself entirely to astronomy.
Baily had in 1820 been instrumental in the founding of the Royal Astronomical Society. In 1827 he received the Gold Medal of the Royal Astronomical Society for his role in the creation of a catalog of 2881 stars ( Catalogue of 2881 Stars ).
On his initiative, the revision of the Nautical Almanac goes back in 1829. In 1837 he recommended the revision and summary of the star catalogs of Jérôme Lalande Nicolas Louis de Lacaille and containing 57,000 stars.
It was the British Association 's Catalogue of 8377 Stars, which was published in 1845. In addition sighted and he revised the older catalogs and records of Ptolemy, Ulugh Beg, Tobias Mayer, Tycho Brahe, Edmond Halley and Hevelius.
During the total solar eclipse of 15 May 1836, he observed of Roxburghshire of a phenomenon that is now known as " Baily's beads " or Perlschnurphänomen. Caused it is by unevenness of the lunar edge, which shortly before and after the total phase " light beads " are visible. His published about vivid description was the catalyst for the transmission of " darkness expeditions " in the world. Baily even still watching from the total solar eclipse of July 8, 1842 by Pavia.
He completed Henry Foster's pendulum experiment for the determination of the Earth flattening, which he defined as 1/ 289, 48. His work on the determination of the mean density of the planet earth by the method of Henry Cavendish gave a value of 5.66 g / cm ³.