high-performance mirror
51Ritchey-Chrétien telescope — The Ritchey Chrétien telescope or RCT is a specialized Cassegrain telescope designed to eliminate coma, thus providing a relatively large field of view as compared to a more conventional configuration. An RCT has a hyperbolic primary and a… …
52Mercury Grand Marquis — Manufacturer Ford Motor Company Model years 1983–2011 Predecessor M …
53Fashions — ▪ 2009 The faltering global economy determined the direction of fashion during 2008. Initially, the euro s significant appreciation against the dollar proved a boon to style conscious travelers who, visiting the U.S. from abroad as the year …
54RRZE — Das Regionale RechenZentrum (RRZE) ist der IT Dienstleister der Universität Erlangen Nürnberg. Bild des RRZE Gebäudes mit Informatikhochhaus im Hintergrund Es unterstützt im Rahmen des Regionalkonzepts weitere Hochschulen und Universitäten in der …
55space 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… …
56aerospace industry — Introduction assemblage of manufacturing concerns that deal with vehicular flight within and beyond the Earth s atmosphere. (The term aerospace is derived from the words aeronautics and spaceflight.) The aerospace industry is engaged in the …
57naval ship — Introduction the chief instrument by which a nation extends its military power onto the seas. Warships protect the movement over water of military forces to coastal areas where they may be landed and used against enemy forces; warships… …
58Natural scientific research in Canada — This article outlines the history of natural scientific research in Canada, including mathematics, physics, astronomy, space science, geology, oceanography, chemistry, biology, medical research and psychology. The social sciences are not treated… …
59Hard disk drive — Hard drive redirects here. For other uses, see Hard drive (disambiguation). Hard disk drive Mechanical interior of a modern hard disk drive Date invented 24 December 1954 [1] …
60Rocket — This article is about vehicles powered by rocket engines. For other uses, see Rocket (disambiguation). A Soyuz U, at Baikonur Site 1/5 A rocket is a missile, spacecraft, aircraft or other vehicle which obtains thrust from a rocket engi …
