1780s in Science - Comet Encke, Supplementum Plantarum, 1780s in Archaeology, de Fructibus Et Seminibus Plantarum, 1781 in Science (Paperback)

Chapters: Comet Encke, Supplementum Plantarum, 1780s in Archaeology, de Fructibus et Seminibus Plantarum, 1781 in Science, 1783 in Science, 1785 in Science, 1787 in Paleontology, 1789 in Science, 1787 in Science, 1784 in Science, 1788 in Science, 1782 in Science, 1786 in Science, Hortus Kewensis, 1780 in Science, 1784 in Paleontology, Catalogue of Nebulae. Source: Wikipedia. Pages: 47. Not illustrated. Free updates online. Purchase includes a free trial membership in the publisher's book club where you can select from more than a million books without charge. Excerpt: Comet Encke or Encke's Comet (official designation: 2P/Encke) is a periodic comet that completes an orbit of the sun once every three years the shortest period of any known comet. It was first recorded by Pierre Mechain in 1786, but it was not recognized as a periodic comet until 1819 when its orbit was computed by Johann Franz Encke; like Halley's Comet, it is unusual in being named after the calculator of its orbit rather than its discoverer. As its official designation implies, Encke's Comet was the first periodic comet discovered after Halley's Comet (designated 1P/Halley). Its orbit was calculated by Johann Franz Encke, who, through laborious calculations was able to link observations of comets in 1786 (designated 2P/1786 B1), 1795 (2P/1795 V1), 1805 (2P/1805 U1) and 1818 (2P/1818 W1) to the same object. In 1819 he published his conclusions in the journal Correspondance astronomique, and predicted correctly its return in 1822 (2P/1822 L1). The diameter of the nucleus of Encke's Comet is 4.8 km Comets are on unstable orbits that evolve over time due to perturbations and outgassing. Given Encke's low orbital inclination near the ecliptic and brief orbital period of 3 years, the orbit of Encke is frequently perturbed by the inner planets. The failed CONTOUR mission was launched to study this comet, and also Schwassmann-Wachmann 3. On April 20, 2007, the tail ...More: http: //booksllc.net/?id=48031