3 articles for "Spectral"

Stars are grouped into Spectral Classes, according to their spectra. Various classification schemes have been proposed, but the one most generally accepted evolved from work done at the Harvard Observatory. It is based on the appearance of the photographic region of a star's spectrum, from green to ultra-violet. Each class is denoted by a capital letter (O, B, A, F, G, K, and M), and are intended to represent stages of stellar evolution. Each class is subdivided by placing a numeral after the capital leter (e.g., B8 and K2). Over 90% of all stars fall into four classes: A, F, G, and K.

See also: ♦ Light Spectrum

A means for classifying bodies by the quality of their energy output.

See also: ♦ Light Spectrum

A series of spectral classes of stars arranged in order of decreasing temperature.

See also: ♦ Spectral Class