Centaurus

Cen · genitive Centauri · southern sky

The Centaurus figure as the IAU defines it, drawn looking south with east to the left — the orientation you see standing outside.

At a glance

Catalogued stars
284
Visible to the eye
283 stars
Brightest star
Alpha Centauri A (-0.27)
Best seen
April
Declination span
-60.8° to -36.4°
Nearest star
Proxima Centauri · 4.2 ly

Visible from everywhere south of about 29°N.

When and where to look for Centaurus

Centaurus crosses the meridian — its highest point in the sky — at local midnight around April, which makes the months from March to May the easiest time to find it in the evening. It spans declinations -60.8° to -36.4°, so visible from everywhere south of about 29°N.

The quickest way to find it is to open the live AR sky map and point your phone at the sky — if Centaurus is above your horizon right now, its figure is drawn in the position it genuinely occupies above you.

Brightest stars in Centaurus

StarMagTypeDistance
Alpha Centauri A-0.27G2V4.4 ly
HadarBeta Centauri0.61B1III390 ly
TolimanAlp2Cen1.35K1V4.3 ly
Menkent5The Cen2.06K0IIIb58.8 ly
Gam Cen2.20A1IV130.1 ly
Eps Cen2.29B1III427.5 ly

Magnitude runs backwards: lower numbers are brighter, and anything below about 6.5 is beyond the naked eye under a dark sky.

What Centaurus is made of

The catalogue lists 284 stars within Centaurus, of which 283 are magnitude 6.5 or brighter — the limit of what an unaided eye picks up under a genuinely dark sky. The rest need binoculars or a telescope.

Spectral make-up

O2
B82
A58
F25
G33
K67
M17

Spectral class is a temperature ordering, running from O at around 30,000 K down to M below 3,500 K. A constellation is a direction, not a group, so this is simply what happens to lie along that line of sight.

The closest catalogued star in this direction is Proxima Centauri at 4.2 light years. The most distant is HD 119159 at roughly 2,886 light years — stars that appear side by side here are nothing of the sort.

Deep-sky objects in Centaurus

  • Omega Centauri — globular cluster

These are marked on the sky map, so you can see where they sit relative to the constellation figure in real time.

Nearby constellations