Why is aldebaran red

Aldebaran has evolved off the main sequence stage of its life and exhausted its supply of hydrogen fuel in its core. Because of this, the star has brightened and expanded its radius. The origin of Aldebaran is still a mystery to scientists.

It is speculated that it formed around 6. Its origins remain unknown to this day. It is thus around 44 times bigger than our sun. Though it is much bigger than our sun, it has only 1. This small variability cannot be seen with the naked eye, but it puts Aldebaran in the low irregular type LB stars.

Since its core collapsed into a degenerate helium core, it has ignited a shell of hydrogen outside its core. Aldebaran is losing its mass at about one entire Earth per This creates an extended molecular outer atmosphere where the temperatures are cool enough for molecules of gas to form.

This region is 2. Outside this sphere, its stellar winds continue to expand forming a roughly spherical astrosphere of around 1. A highly evolved, orange-red giant star, Aldebaran A is still much smaller than the red supergiant Betelgeuse , at left. Aldebaran, or Alpha Tauri, is a binary star system located around The star lies in the central part Its proper name, Aldebaran, is derived from the Arabic "Al Dabaran" for the Follower because the star appears to track the night time movement of the Pleiades "Seven Sisters" star cluster.

This first magnitude star is the 13th brightest in Earth's night sky. According to Robert Burnham, Jr. The system is a member of the Hyades group. In , a team of astronomers announced the tentative discovery of a giant planet companion "b" to Aldebaran A more details below. The discovery has yet to be confirmed, and some astronomers suspect that the radial velocity variations may actually reflect a long-term oscillation in Star A itself. See an animation of the orbit of this possible substellar object around Aldebaran, with a table of basic orbital and physical characteristics.

The star may have a mass between one and 2. It also has around times Sol's luminosity based on a Johnson Vmag of 0. Aldebaran A is estimated to have between 47 to percent as enriched than Sol with elements heavier than hydrogen "metallicity" based on its abundance of iron Cayrel de Strobel et al, , page Before the star evolved out of the main sequence, it may have been a spectral type A dwarf Hatzes and Cochran, Aldebaran A is believed to have evolved into helium-burning "clump" giant.

The star was noted and named in Chinese, Roman and Hindu astronomy, among other cultures. Aldebaran would have been hard to miss for the ancients, given that Taurus is very visible in the winter. The bull, in fact, is one of the oldest documented constellations.

Its origins stretch back at least as far as the Bronze Age. At 65 light-years away, the star is practically a neighbor to Earth. Its apparent magnitude is about 0. Aldebaran's location is:. Joseph McCarthy was hunting for communists. A red giant star, Aldebaran has a radius 44 times that of the sun.

If it replaced the sun, the star would extend almost to the orbit of Mercury. To the right of the Hyades is the wonderful Pleiades star cluster, much brighter and more compact than the Hyades. This cluster is about The naked eye typically can see at least six stars.

The view is incredible in binoculars.