The Hyades, Melotte 25, is a beautiful open cluster in Taurus that is easily visible to the unaided-eye. Hold your mouse cursor over the image to see identifications.

Designated as number 25 in the Melotte list of star clusters, the Hyades is 5 degrees in diameter. Located 151 light-years away, it is the nearest cluster after the Ursa Major Moving Cluster. The Hyades is believed to be 790 million years old. It is comprised of 100 stars that formed at the same time, and have the same chemical composition and the same common motion through space.

Brilliant Aldebaran (Alpha Tauri), the brightest star in the image, is a 0.9 magnitude red-giant star. It appears to be part of the cluster, but is not actually a member. Aldebaran is located only 60 light-years away and lies in front of the cluster along the same line of sight.

Theta 1 and Theta 2 Tauri are two close stars that are an interesting test of vision as they are separated by five and a half arcminutes. This is compared to Mizar and Alcor, the double in the handle of the Big Dipper which are separated by eleven and three-quarter arcminutes.

The two Thetas are located in the bottom arm of the "V" shape that makes the Hyades (seen on its side here with the point of the "V" to the right), halfway between Aldebaran and Gamma Tauri in the point.

The other bright stars that make up the "V" are Epsilon on the top left end of the "V" opposite Aldebaran, and Delta 1 and Delta 2, also in the top arm of the "V" opposite the two Thetas.

Aldebaran, along with Theta 1, Gamma, Delta 1, and Epsilon, are all red-giant stars.

The "V"-shaped Hyades cluster makes up the head of the constellation of Taurus the Bull.

Smaller open cluster NGC 1647 is on the left in the image, some 45 arcminutes in diameter shining at magnitude 6.4.

North is to the upper left in the above image.

Hyades Catalogs: Mel 25, OCL 456 Common Name: Hyades Object Type: Open Cluster Magnitude: 0.5 Size: 330' Constellation: Taurus Image Field Centered At: RA: 04h 32m 52s Dec: +17° 42' 02"