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Andromeda Galaxy

(Encyclopedia)Andromeda Galaxy, cataloged as M31 and NGC 224, the closest large galaxy to the Milky Way and the only one visible to the naked eye in the Northern Hemisphere. It is also known as the Great Nebula in ...

optical sensing

(Encyclopedia)optical sensing, in general, any method by which information that occurs as variations in the intensity, or some other property, of light is translated into an electric signal. This is usually accompl...

blueprint

(Encyclopedia)blueprint, white-on-blue photographic print, commonly of a working drawing used during building or manufacturing. The plan is first drawn to scale on a special paper or tracing cloth through which lig...

holography

(Encyclopedia)holography hŏlŏgˈrəfē, hō– [key], method of reproducing a three-dimensional image of an object by means of light wave patterns recorded on a photographic plate or film. Holography is sometimes...

Text of the Constitution of the United States

(Encyclopedia)Text1 of the Constitution of the United States Preamble Article I Article II Article III Article IV Article V Article VI Article VII Amendment I Amendment II Am...

Biot, Jean Baptiste

(Encyclopedia)Biot, Jean Baptiste zhäN bätēstˈ byō [key], 1774–1862, French physicist, grad. École Polytechnique (1797). He taught mathematics at Beauvais before becoming (1800) professor of mathematical ph...

black hole

(Encyclopedia)black hole, in astronomy, celestial object of such extremely intense gravity that it attracts everything near it and in some instances prevents everything, including light, from escaping. The term was...

camera

(Encyclopedia)CE5 Image formed by a camera camera, lightproof box or container, usually fitted with a lens, which gathers incoming light and concentrates it so that it can be directed toward the film (in an opt...

silver chloride

(Encyclopedia)silver chloride, chemical compound, AgCl, a white cubic crystalline solid. It is nearly insoluble in water but is soluble in a water solution of ammonia, potassium cyanide, or sodium thiosulfate (“h...

color index

(Encyclopedia)color index, in astronomy, difference in an object's brightness as recorded between any two well-defined bands of the electromagnetic spectrum by using optical filters of different colors. If blue and...