Alpha Crucis
Related Category: Astronomy: Stars
(l´f kr´ss): see Acrux.
More on Alpha Crucis
Acrux - (´krks) [from the Bayer designation &agr; Crucis], brightest star in the constellation Crux (Southern Cross); 1992 position R.
Acrux (Alpha Crucis)
The twelfth brightest star in the sky, the southernmost first magnitude star, and the brightest and southernmost star in Crux. Acrux is a multiple system.
Alpha Crucis has an apparent proper motion of 236º. (That is, from our viewpoint, it seems to be moving very slowly in this direction.) Others in this constellation with similar motions, and therefore part of a moving star cluster, are beta, delta, ...
ACRUX (Alpha Crucis). Among the most famous constellations in the sky is a "modern" one that is quite invisible from most of the populated northern hemisphere: Crux, the Southern Cross.
The principal star in Crux is [3020] alpha Crucis, also known as Acrux (contraction of "alpha" and "Crux"), a binary star about 360 light-years distant. It is the twelfth brightest star in the sky, with a visual magnitude 0.77.
The constellation's brightest star is sometimes called Acrux, a name applied by navigators from its scientific designation Alpha Crucis. It is actually a double star, divisible through small telescopes into two sparkling blue-white points.
From the top of the cross Gacrux(gamma crucis) trace a line south to Acrux (alpha crucis) and continue about 4.5 times that distance and you will get near the celestial south pole.
The star lies in the part (12:31:10.0-57:6:47.6, ICRS 2000.0) or "top" of Constellation Crux (see chart and photo), the Southern Cross -- northwest of Mimosa (Beta Crucis), northeast of Delta Crucis, and north of Acrux (Alpha Crucis).
At the time of Christ, however, it was visible from the latitude of Jerusalem (almost 32 degrees N). Crux points almost due north-south. You you follow the line south through Gamma and Alpha Crucis, ...
 See also: Sky, Acrux, Constellation, Star, Magnitude
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