average core diameter
41Laser — For other uses, see Laser (disambiguation). United States Air Force laser experiment …
42Uranus — This article is about the planet. For other uses, see Uranus (disambiguation). Uranus   …
43astronomy — /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,… …
44hydrosphere — /huy dreuh sfear /, n. the water on or surrounding the surface of the globe, including the water of the oceans and the water in the atmosphere. [1885 90; HYDRO 1 + SPHERE] * * * Discontinuous layer of water at or near the Earth s surface. It… …
45Milky Way Galaxy — Large spiral galaxy (roughly 150,000 light years in diameter) that contains Earth s solar system. It includes the multitude of stars whose light is seen as the Milky Way, the irregular luminous band that encircles the sky defining the plane of… …
46Dye 3 — is an ice core site and previously part of the Distant Early Warning (DEW) line, located at (65°11′N 43°49′W / 65.183°N 43.817°W / 65.183; 43.817 ( …
47Neptune — This article is about the planet. For other uses, see Neptune (disambiguation). Neptune   …
48Pluto — This article is about the dwarf planet. For other uses, see Pluto (disambiguation). Pluto   …
49nuclear reactor — Physics. reactor (def. 4). Also called nuclear pile. [1940 45] * * * Device that can initiate and control a self sustaining series of nuclear fission reactions. Neutrons released in one fission reaction may strike other heavy nuclei, causing them …
50Ganymede (moon) — Ganymede Image of Ganymede s anti Jovian hemisphere taken by the Galileo probe. Lighter surfaces, such as in recent impacts, grooved terrain and the whitish north polar cap at upper right, are enriched in water ice. Discovery …
