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photosphere

(Encyclopedia)photosphere, luminous, apparently opaque layer of gases that forms the visible surface of the sun or any other star. The photosphere lies between the dense interior gases and the more attenuated gases...

transistor

(Encyclopedia)CE5 Simple transistor circuit transistor, three-terminal, solid-state electronic device used for amplification and switching. It is the solid-state analog to the triode electron tube; the transist...

mirage

(Encyclopedia)mirage mĭräzhˈ [key], atmospheric optical illusion in which an observer sees in the distance a nonexistent body of water or an image, sometimes distorted, of some object or of a complete scene. Exa...

plating

(Encyclopedia)plating, application of a plate, or coat, of metal to a surface for decoration, reflection of light, protection against corrosion, or increased wearing quality. The practice is of ancient origin: gild...

firebrick

(Encyclopedia)firebrick, brick that can withstand high temperatures, used to line flues, stacks, furnaces, and fireplaces. In general, such bricks have high melting points that range from about 2,800℉ (1.540℃) ...

Webb Space Telescope

(Encyclopedia)Webb Space Telescope or James Webb Space Telescope (JWST), is an infrared space telescope, the largest in space at its launc...

ceilometer

(Encyclopedia)ceilometer sēlŏmˈĭtər [key], in aviation and meteorology, automatic instrument used to record ceiling, i.e., the altitude of the lowest cloud layer covering more than half of the sky. The ceilome...

Lockyer, Sir Joseph Norman

(Encyclopedia)Lockyer, Sir Joseph Norman lŏkˈyər [key], 1836–1920, English astronomer, educated on the Continent. One of the first to make a spectroscopic examination of the sun and stars, he devised (1868), i...

laminitis

(Encyclopedia)laminitis lămˌənīˈtĭs [key], also called founder, inflammation of the lamina, the innermost layer of the hoof wall in horses, ponies, and donkeys. Although the condition usually affects only the...

palate

(Encyclopedia)palate pălˈĭt [key], roof of the mouth. The front part, known as the hard palate, formed by the upper maxillary bones and the palatine bones, separates the mouth from the nasal cavity. It is compos...