- Astron. an exceptionally luminous star whose diameter is more than 100 times that of the sun, as Betelgeuse or Antares. Also called supergiant.[1925-30]
* * *Star of very great natural luminosity and relatively enormous size, typically several magnitudes brighter and several times larger than a giant star.Like other classes of stars, they are distinguished in practice by examination of certain lines in their spectra (see spectroscopy). A supergiant may have a diameter several hundred times that of the Sun and a luminosity nearly a million times as great. Supergiants live probably only a few million years, an extremely short life for a star.
* * *any star of very great intrinsic luminosity and relatively enormous size, typically several magnitudes brighter than a giant star and several times greater in diameter. The distinctions between giants (see also giant star), supergiants, and other classes are made in practice by examining certain lines in the stars' spectra. A star classed as a supergiant may have a diameter several hundred times that of the Sun and a luminosity nearly 1,000,000 times as great. Supergiants are tenuous stars, and their lifetimes are probably only a few million years, extremely short on the scale of stellar evolution.
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supergiant star — noun see supergiant 2 * * * Astron. an exceptionally luminous star whose diameter is more than 100 times that of the sun, as Betelgeuse or Antares. Also called supergiant. [1925 30] * * * su|per|gi|ant «SOO puhr JY uhnt», noun, or supergiant star … Useful english dictionary
star — starless, adj. /stahr/, n., adj., v., starred, starring. n. 1. any of the heavenly bodies, except the moon, appearing as fixed luminous points in the sky at night. 2. Astron. any of the large, self luminous, heavenly bodies, as the sun, Polaris,… … Universalium
Star — For other uses, see Star (disambiguation) … Wikipedia
supergiant — /sooh peuhr juy euhnt/, n. 1. Astron. See supergiant star. 2. an extremely large or powerful person, company, thing, etc. adj. 3. extremely large; immense. [1925 30; SUPER + GIANT] * * * … Universalium
supergiant — [so͞o′pər jī΄ənt] n. an immense and extremely luminous star, as Betelgeuse or Antares, that has a diameter at least 100 times that of the sun and that is 100 to more than 10,000 times as bright … English World dictionary
Supergiant — Supergiants are among the most massive stars. In the Hertzsprung Russell diagram they occupy the top region of the diagram. In the Yerkes spectral classification supergiants are class Ia (most luminous supergiants) or Ib (less luminous… … Wikipedia
Star system — This article is about stars in outer space. For the Hollywood star system, see Star system (film). For a system of planets around a star, see Planetary system. A star system or stellar system is a small number of stars which orbit each other,… … Wikipedia
Star designation — Designations of stars (and other celestial bodies) are done by the International Astronomical Union (IAU). Many of the star names in use today were inherited from the time before the IAU existed. Other names, mainly for variable stars (including… … Wikipedia
star cluster — Astron. a number of stars of common origin held together as a group by gravitational attraction. Cf. globular cluster, open cluster, stellar association. * * * ▪ astronomy Introduction either of two general types of stellar assemblages held… … Universalium
star — I (New American Roget s College Thesaurus) n. sun, celestial body; pentagram, asterisk; prima donna, primo uomo, leading man or lady, chief performer; destiny; planet. See indication, drama, repute. II (Roget s IV) n. 1. [A luminous heavenly… … English dictionary for students