He was shot and killed by Hercules with an arrow dipped in Hydra venom. Instead of going to the realm of Hades, Zeus put him in the stars as the constellation "Centaurus" or "Sagittarius".
Alpha Centauri is the brightest star in the Centaurus constellation, the "Centaur".
centaurus
Rigel is in the constellation Orion, not Centaurus. Please check your spelling and, if appropriate, resubmit.
Centaurus
Proxima Centauri is in the constellation Centaurus.
The constellation centaurus was mentioned by Exodus in fourth century BCE, and by Aratus in third century BCE. Cladius Ptolemy catalogued 37 stars in Centaurus in second century AD.
The Right Ascension of Centaurus is roughly between 11h and 15h.
No one is credited with discovering the constellation Centaurus because it can be seen with the naked eye. That said, it was first cataloged in the 2nd century by the Greek astronomer, Ptolemy.
They are not. The Milky Way is a galaxy, the constellation Centaurus is just a man made visual representation of something, and bears no relation to a physical entity.
Obviously, the Milky Way is our Galaxy (or the huge band of stars with that same name) and Centaurus is only a constellation. To be fair to the questioner, Centaurus is in an area of the sky that does contain part of the band of stars called the Milky Way.
Centaurus
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