A star in the Alpha Eridani
system, in the constellation Eridanus
. It's name stems from the Arabic
"river's end". It is one of the brightest stars in the southern hemisphere, it's right behind Procyon
and before Betelgeuse
in brightness, comparatively. Achernar is only visible in the southern hemisphere, easily in the tropics.
Achernar is a hot, blue, B class star with temperatures runnning from 14,500 to 19,300 Kelvin. It is approximately 144 light years away.
A interesting thing about Achernar is that it spins at approximately 250 kilometers per second, creating a belt of emitting gas around it's equator, and thus losing matter at a rate thousands higher than our Sun. Furthermore, Achernar belongs to a peculiar class of stars that show tiny, but periodic light variatons that are mused to be complex pulsations and/or dark "starspots". The exact reason for the fluctuations is not known.
Achernar is 6 to 8 times larger than our Sun, and is destined to one day become a white dwarf like Sirius-B.