the asteroid would then have a period of revolution of about six years
21Earth 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… …
22space exploration — Investigation of the universe beyond Earth s atmosphere by means of manned and unmanned spacecraft. Study of the use of rockets for spaceflight began early in the 20th century. Germany s research on rocket propulsion in the 1930s led to… …
23Earth — This article is about the planet. For other uses, see Earth (disambiguation). Earth   …
24evolution — evolutional, adj. evolutionally, adv. /ev euh looh sheuhn/ or, esp. Brit., /ee veuh /, n. 1. any process of formation or growth; development: the evolution of a language; the evolution of the airplane. 2. a product of such development; something… …
25physical science — physical scientist. 1. any of the natural sciences dealing with inanimate matter or with energy, as physics, chemistry, and astronomy. 2. these sciences collectively. [1835 45] * * * Introduction the systematic study of the inorganic world …
26mathematics — /math euh mat iks/, n. 1. (used with a sing. v.) the systematic treatment of magnitude, relationships between figures and forms, and relations between quantities expressed symbolically. 2. (used with a sing. or pl. v.) mathematical procedures,… …
27Dates of 2004 — ▪ 2005 January It turns out we were all wrong, probably, in my judgment. David Kay, former U.S. chief weapons inspector in Iraq, in testimony to the U.S. Senate Armed Services Committee, January 28 January 1 Haitian Pres. Jean… …
28Princeton University — Latin: Universitas Princetoniensis Motto Dei sub numine viget (Latin) Motto in Engl …
29comet — 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… …
30community ecology — Introduction study of the organization and functioning of communities (community), which are assemblages of interacting populations of the species living within a particular area or habitat. As populations of species interact with one …
