Kaus Australis (Epsilon Sagittarii)
The brightest star in the constellation Sagittarius;
it marks the southern (Latin australis) extremity of the Archer's
bow (Arabic kaus) and is also the lower right star of the Milk Dipper
asterism. Deep in the southern hemisphere, 34° below the celestial equator,
the star is not well known to northerners, though it is the 36th brightest
star in the sky. It has traditionally been called a giant and assigned to
the cool end of B, while others have more recently assigned it to hot-end
class A as a bright giant. In any event, the star is much brighter than
its main sequence counterparts and is clearly in a more advanced state.
It probably has a core of helium that is shrinking and heating as it prepares
to fuse to carbon and oxygen. It may also be a sort of shell
star in which its high rotation speed (over 70 times that of the Sun)
was responsible for creating a shell of gas that hides much of the star
||R.A. 18h 24m 10.3s,
Dec. -34° 23' 5"