Pi Centauri

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π Centauri
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Centaurus
Right ascension 11h 21m 00.41s[1]
Declination −54° 29′ 27.7″[1]
Apparent magnitude (V) +3.90
Characteristics
Spectral type B5Vn
U−B color index −0.59
B−V color index −0.15
Variable type none
Astrometry
Radial velocity (Rv) +9 km/s
Proper motion (μ) RA: -35.85 ± 0.34[1] mas/yr
Dec.: -1.72 ± 0.27[1] mas/yr
Parallax (π) 9.12 ± 0.34[1] mas
Distance 360 ± 10 ly
(110 ± 4 pc)
Absolute magnitude (MV) −1.06
Orbit[2]
Primary π Centauri A
Companion π Centauri B
Period (P) 39.0 ± 0.19 yr
Semi-major axis (a) 0.2263 ± 0.0011"
Eccentricity (e) 0.8530 ± 0.0040
Inclination (i) 19.4 ± 4.9°
Longitude of the node (Ω) 327.8 ± 3.9°
Periastron epoch (T) 2010.410 ± 0.037
Argument of periastron (ω)
(secondary)
340.3 ± 4.0°
Other designations
HR 4390, HD 98718, CP−53°4498, FK5 428, HIP 55425, SAO 238986, GC 15601, CCDM J11210-5429
Database references
SIMBAD data

Pi Centauri (π Cen, π Centauri) is a binary star in the constellation Centaurus. It is approximately 360 light years from Earth.

Both components are blue-white B-type main sequence dwarfs. The primary π Centauri A, has an apparent magnitude of +4.3, while the apparent magnitude of its companion, π Centauri B, is +5.0. The two stars orbit around their common centre of mass once every 39 years.[2] The semi-major axis of the companion is 0.23 arcseconds on the sky.

References[edit]