Hyades

Hyades, prominent star cluster visible to the naked eye, whose apparent “V” shape marks out the head of the constellation Taurus (“the bull”). The Hyades is the second-closest star cluster to our solar system, lying some 150 light years away. The cluster contains around 200 stars: notably, however, the bright red giant Aldebaran is not a member, but lies closer to us along the same line of sight. The Hyades stars formed about 650 million years ago and have a common motion through space. Spectroscopic analysis has allowed the Hyades’ physical properties to be determined, and extrapolation of these to similar stars in more remote clusters allows the distances of the latter to be determined: the Hyades thus provide an important measurement of distance in studies of the Milky Way.