Alpha Octantis

α Octantis

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Octans
Right ascension	21h 04m 43.0645s[1]
Declination	−77° 01′ 25.562″[1]
Apparent magnitude (V)	5.15[1]
Characteristics
Spectral type	F4III / F5III (spectroscopic binary)[2]
U−B color index	+0.13[3]
B−V color index	+0.49[3]
Variable type	EB[4]
Astrometry
Radial velocity (Rv)	45.0 ± 2[1] km/s
Proper motion (μ)	RA: 13.83[1] mas/yr Dec.: −369.37[1] mas/yr
Parallax (π)	22.07 ± 0.57[1] mas
Distance	148 ± 4 ly (45 ± 1 pc)
Absolute magnitude (MV)	1.87[5]
Other designations
α Oct, Alpha Octantis, Alpha Oct, CD−77 1053, CPD−77 1474, FK5 787, GC 29343, HD 199532, HIP 104043, HR 8021, LTT 8327, NLTT 50332, PPM 374864, SAO 257879.[1]
Database references
SIMBAD	data

Alpha Octantis (Alpha Oct, α Octantis, α Oct) is a star in the constellation of Octans. It has an overall apparent visual magnitude of approximately 5.15 and is a spectroscopic binary star which consists of two giant stars, each with spectral type F, orbiting each other with a period of just over 9 days.^[1][2] The pair has also been classified as a Beta Lyrae-type eclipsing binary system.^[4]

References

1. ^ ^{a b c d e f g h i} V* alf Oct -- Spectroscopic binary, database entry, SIMBAD. Accessed on line September 4, 2008.
2. ^ ^{a b} The double-lined binary alpha Octantis, William Buscombe and Pamela M. Morris, The Observatory 80 (February 1960), pp. 28–29, Bibcode: 1960Obs....80...28B.
3. ^ ^{a b} HR 8021, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 4, 2008.
4. ^ ^{a b} alf Oct, database entry, The combined table of GCVS Vols I-III and NL 67-78 with improved coordinates, General Catalogue of Variable Stars, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line September 4, 2008.
5. ^ From apparent magnitude and parallax.

External links

• Alpha Octantis, Jim Kaler, Stars.