Beta Herculis

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Beta Herculis (β Her / β Herculis) is a star in the constellation Hercules. It also has the traditional name Kornephoros ("club carrier").

Beta Herculis has apparent magnitude +2.7 and belongs to the spectral class K0. It is in the Main Seqeunce stage of life. It is approximately 148 light years from Earth. KORNEPHOROS (Beta Herculis). Some constellations, exemplified by Orion, stand out brilliantly among their neighbors. But brightness does not necessarily mean unimportance, as testified by Hercules, one of the oldest and best known constellations in the sky even though its brightest star, Kornephoros, is third magnitude (albeit at the bright end of third, 2.77). The constellation that honors the Greek hero was originally known as "the Kneeler," a man of ancient though unknown significance. Though Kornephoros is the brightest star of the constellation, it lost the Alpha designation to Rasalgethi as that star is in the Kneeler's head (the name's meaning). As a result, Kornephoros received the consolation prize of Beta. Instead of referring to the Kneeler, Kornephoros, which from Greek means the "club-bearer," refers to Hercules himself through one of his mighty weapons. Like Alphecca in Corona Borealis and Graffias in Scorpius, Kornephoros has two proper names, the other "Rutilicus," a corruption of a Latin word meaning "armpit" and referring to the man of the constellation. In reality Kornephoros is a yellow, relatively cool (4900 Kelvin) class G (G7) giant 148 light years away with a luminosity 175 times that of the Sun. From these data we find a radius nearly 20 times solar as befits a giant of its stature. The star is similar to the main component of Capella, though a bit warmer, and 60 percent brighter. From its temperature and luminosity it is also, at about three solar masses, somewhat more massive. As a giant the star is evolving rapidly, and is now most likely quietly fusing the helium in its core into carbon and oxygen, having begun life (when it was fusing hydrogen) as a hot "main sequence" class B star somewhat like Zubeneschamali. In fact the star is just what Zubeneschamali will look like in 200 or so million years. Little else distinguishes Kornephoros. It is a very normal star for its state of age. It is a significant source of X-rays that reveal some magnetic activity, and has a nitrogen abundance enhanced relative to carbon (also not unusual). Like so many other stars it also has a companion, but one unseen and known only through the gravitational effect it has on the visible star (causing it to move back and forth along the line of sight). The companion, about which almost nothing is known, probably has a mass a bit higher than that of the Sun. Kornephoros is not big enough to explode, and will finally die as a fairly massive white dwarf rather like the companion to Sirius. .

Coordinates (equinox J2000)