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81Rings of Neptune — The scheme of Neptune s ring moon system. Solid lines denote rings; dashed lines denote orbits of moons. The rings of Neptune consist primarily of five principal rings predicted in 1984 by André Brahic and imaged in 1989 by the Voyager 2… …
82Telescopic sight — Scope redirects here. For other uses, see Scope (disambiguation). View through a 4x rifle scope. A telescopic sight, commonly called a scope, is a sighting device that is based on an optical refracting telescope. They are equipped with some form… …
83Pluto — /plooh toh/, n. 1. Class. Myth. a name given to Hades, under which he is identified by the Romans with Orcus. 2. Astron. the planet ninth in order from the sun, having an equatorial diameter of about 2100 miles (3300 km), a mean distance from the …
84Hertzsprung , Ejnar — (1873–1967) Danish astronomer Hertzsprung was born in Frederiksberg, Denmark, the son of a senior civil servant who had a deep interest in mathematics and astronomy but who was anxious to see that his son received a more practical education.… …
85ZX Spectrum graphic modes — The ZX Spectrum is generally considered to have limited graphical capabilities in comparison to other home computers of the same era such as the Commodore 64, largely due to its lack of a dedicated graphics chip. Nevertheless, throughout its… …
86Quebec — This article is about the Canadian province. For the province s capital city, see Quebec City. For other uses, see Quebec (disambiguation). Coordinates …
87Gravitational lensing formalism — In general relativity, a point mass deflects a light ray with impact parameter b by an angle hat{alpha} = frac{4GM}{c^2b}. A naïve application of Newtonian gravity can yield exactly half this value, where the light ray is assumed as a massed… …
88insect — insectival /in sek tuy veuhl/, adj. /in sekt/, n. 1. any animal of the class Insecta, comprising small, air breathing arthropods having the body divided into three parts (head, thorax, and abdomen), and having three pairs of legs and usually two… …
89Milky 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… …
90Plasma display — A plasma display panel (PDP) is a type of flat panel display now commonly used for large TV displays (typically above 37 inch or 940 mm). Many tiny cells located between two panels of glass hold an inert mixture of noble gases. The gas in the… …
