Algol Star
Wiley Book of Astronomy:
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Algol star
A type of eclipsing binary, named after the prototype, Algol, that has periods of constant or near-constant brightness between minima, indicating that the two stars form a close binary of the detached or semidetached kind. Thousands of examples are known, with periods ranging from about 5 hours to 30 years and brightness variations of up to several magnitudes. In most cases where mass transfer takes place, it is by direct accretion rather than by an accretion disk. However, an extreme group of eclipsing, mass-transferring binaries, known as W Serpentis stars or “hyperactive Algols,” does have accretion disks and may be in a pre-Algol-type stage. Algol stars are among the most important kind of star systems in terms of the information they provide on stellar masses and sizes.
Oxford Dictionary of Astronomy:
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Algol Star
A type of eclipsing binary with periods of constant (or almost constant) brightness between well-defined eclipses; abbr. EA. This feature is an indication that the system is a detached binary or semidetached binary. The secondary minimum may be invisible. Periods range from 0.2 to 10 000 days, and the amplitudes may reach several magnitudes. If mass transfer occurs, the material is accreted directly on to the hot star, not via an accretion disk. Mass transfer via an accretion disk does occur in the W Serpentis stars, which have wider separations and may be pre-Algol stars. The terms W Serpentis star and Serpentid are sometimes used to include both groups of stars.
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Wiley Book of Astronomy
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Mentioned in
Hermann Karl Vogel
(German astronomer)
Year 1782
(in Science & Technology)
Year 1669
(in Science & Technology)
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