Hyades

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Hyades

(hī`ədēz), in astronomy, open star clusterstar cluster,
a group of stars near each other in space and resembling each other in certain characteristics that suggest a common origin for the group. Stars in the same cluster move at the same rate and in the same direction.
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 in the constellation Taurus, located immediately to the right of the bright star Aldebaran. The cluster is about 130 light-years from the earth. It consists of about 100 stars all moving in the same direction. Its shape is that of an oblate spheroid, with most of the stars lying within 20 light-years of the center. Most of the stars in this cluster are of spectral classspectral class,
in astronomy, a classification of the stars by their spectrum and luminosity. In 1885, E. C. Pickering began the first extensive attempt to classify the stars spectroscopically.
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 G and K and are average in size, with temperatures that are comparable to that of the sun. The nebular variable star T Tauri is part of this cluster. The Hyades is important as a fundamental calibration point in the distance scale of the universe. Because it is one of the closest of the open clusters, measurements of parallaxes of its stars as well as the relationship between the apparent and absolute magnitudes of some of its member stars yield similar distance results. In 1908 L. Boss discovered that the proper motions of all the Hyades stars were converging as an effect of perspective, and that their motions were really parallel. Once the convergent point for the cluster was established, the distance could be calculated. With the distance to this cluster known accurately, absolute magnitudes for its members could be determined. Thus the Hyades stars are used as calibration for similar stars in far more distant clusters.

Hyades,

in Greek mythology, nymphs; daughters of Atlas and Aethra. They cared for both Zeus and Dionysus as infants. In recognition of these services, they were placed among the stars of the constellation Taurus, where their rising and setting corresponded to the rainy seasons.

Hyades

(hÿ -ă-deez) An open cluster of over 200 stars in the constellation Taurus. It is the nearest open cluster, about 46 parsecs away, and is scattered over an area of about 6°. Its brightest members form a V-shaped group that is visible to the naked eye, with Aldebaran in the foreground (but not a member). Its age is about 600 million years.

Hyades

[′hī·ə‚dēz]
(astronomy)
A V-shaped open star cluster about 150 light-years from the sun, which appears in the constellation Taurus near the star Aldebaran.

Hyades

seven daughters of Atlas, entrusted with the care of the infant Dionysus. [Gk. Myth.: Howe, 134]
See: Nymph