Astronomy — (from the Greek words astron (ἄστρον), star , and nomos (νόμος), law ) is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earth s atmosphere (such as the cosmic… … Wikipedia
Astronomy in medieval Islam — An 18th century Persian Astrolabe, kept at The Whipple Museum of the History of Science in Cambridge, England. Islamic astronomy or Arabic astronomy comprises the astronomical developments made in the Islamic world, particularly during the… … Wikipedia
extragalactic — adjective Etymology: International Scientific Vocabulary Date: 1851 originating or existing outside the Milky Way galaxy; also of or relating to extragalactic space < extragalactic astronomy > … New Collegiate Dictionary
extragalactic — adjective a) Originating outside of the Milky Way galaxy. Extragalactic astronomy is the study of things outside the Milky Way b) Originating outside of a galaxy See Also: extrasolar, extraplanetary, extraterrestrial … Wiktionary
Extragalactic cosmic ray — Extragalactic cosmic rays are very high energy particles that flow into our solar system from beyond our galaxy. The energies these particles possess are in excess of 1015 eV. Origin Unlike solar or galactic cosmic rays, little is known about the … Wikipedia
astronomy — /euh stron euh mee/, n. the science that deals with the material universe beyond the earth s atmosphere. [1175 1225; ME astronomie ( < AF) < L astronomia < Gk. See ASTRO , NOMY] * * * I Science dealing with the origin, evolution, composition,… … Universalium
ASTRONOMY — In the Bible Although the Bible contains no explicit mention of the science of astronomy, it nevertheless has many references to topics such as the laws of the heavens (Jer. 31:34 (35); 33:25; Job 38:33) and the movements of the sun and the moon… … Encyclopedia of Judaism
extragalactic nebula — noun (astronomy) a collection of star systems; any of the billions of systems each having many stars and nebulae and dust extragalactic nebula is a former name for galaxy • Syn: ↑galaxy • Derivationally related forms: ↑galactic (for: ↑gal … Useful english dictionary
extragalactic — [ˌɛkstrəgə laktɪk] adjective Astronomy occurring or originating outside the Milky Way galaxy … English new terms dictionary
Outline of astronomy — Mauna Kea in Hawaii is one of the world s premier observatory sites. Pictured is the W. M. Keck Observatory, an optical interferometer. The following outline is provided as an overview of and topical guide to astronomy: Astronomy – studies the… … Wikipedia
