Epoch J2000 Equinox J2000 |Right ascension||21h 08m 46.8s|
|Declination||-88° 57′ 23″| |Apparent magnitude (V)||5.42|
|Spectral type||F0 III| |U−B color index||0.13| |B−V color
index||0.27| |Variable type||Delta Scuti| |Radial velocity
(Rv)||+11.9 km/s| |Proper motion (μ)||RA: 25.96 mas/yr Dec.:
5.02 mas/yr |Parallax (π)||12.07 ± 0.48 mas| |Absolute magnitude
(MV)||0.83| Sigma Octantis (σ Oct, σ Octantis) is a magnitude
5.6 star in the constellation Octans most notable for being the
current South Star. Sigma Octantis is approximately 270 light
years from Earth, and is classified as a giant, with a spectral
type of F0 III. It is a Delta Scuti variable, with magnitude
varying by about 0.03 magnitudes over 2.3 hours. Southern pole
star  Sigma Octantis is the southern pole star, whose
counterpart is Polaris, the current North Star. To an observer
in the southern hemisphere, Sigma Octantis appears almost
motionless and all the other stars in the Southern sky appear to
rotate around it. It is part of a small "half