jupiter's atmosphere is hydrogen and helium
81Earth Sciences — ▪ 2009 Introduction Geology and Geochemistry The theme of the 33rd International Geological Congress, which was held in Norway in August 2008, was “Earth System Science: Foundation for Sustainable Development.” It was attended by nearly… …
82Aerobot — An aerobot is an aerial robot, usually used in the context of an unmanned space probeWhile work has been done since the 1960s on robot rovers to explore the Moon and other worlds in the Solar system, such machines have limitations. They tend to… …
83moon — mooner, n. moonless, adj. /moohn/, n. 1. the earth s natural satellite, orbiting the earth at a mean distance of 238,857 miles (384,393 km) and having a diameter of 2160 miles (3476 km). 2. this body during a particular lunar month, or during a… …
84extraterrestrial life — Introduction life that may exist or may have existed in the universe outside of Earth. The search for extraterrestrial life encompasses many fundamental scientific questions. What are the basic requirements for life? Could life have arisen… …
85Neon — This article is about the noble gas. For other uses, see Neon (disambiguation). fluorine ← neon → sodium …
86Titan (moon) — Titan Titan in 2005 by Cassini spacecraft Discovery Discovered by Christiaan Huygens …
87Xenon — (PronEng|ˈzɛnɒn [Xenon, entry in the Oxford English Dictionary, prepared by J. A. Simpson and E. S. C. Weiner, vol. 20, second edition, Oxford: Clarendon Press, 1989. ISBN 0 19 861232 X (vol. 20), ISBN 0 19 861186 2 (set.)] or IPAlink en|ˈziːnɒn… …
88Timeline of astronomy — Timeline of astronomy2500 BCMany ancient sites are thought to have astronomical significance, such as the Ancient Egyptian pyramids, Harappan shell instruments, British megaliths, and buildings in China and Latin America.In Lothal, the ancient… …
89comet — cometary /kom i ter ee/, cometic /keuh met ik/, cometical, adj. cometlike, adj. /kom it/, n. Astron. a celestial body moving about the sun, usually in a highly eccentric orbit, consisting of a central mass surrounded by an envelope of dust and… …
90Moon — /moohn/, n. Sun Myung /sun myung/, born 1920, Korean religious leader: founder of the Unification Church. * * * Sole natural satellite of Earth, which it orbits from west to east at a mean distance of about 238,900 mi (384,400 km). It is less… …
