en Kappa2 Apodis

κ² Apodis
	Location of κ2 Apodis (circled)
Observation data; Epoch J2000 Equinox J2000
Constellation	Apus
Right ascension	15h 40m 21.33360s
Declination	–73° 26′ 48.0648″
Apparent magnitude (V)	5.65
Characteristics
Spectral type	B7 III-IV + K0 V
U−B color index	–0.38
B−V color index	–0.04
Astrometry
Radial velocity (Rv)	–19.0 km/s
Proper motion (μ)	RA: –12.36 mas/yr ; Dec.: –20.56 mas/yr
Parallax (π)	4.18 ± 0.28 mas
Distance	780 ± 50 ly ; (240 ± 20 pc)
Absolute magnitude (MV)	−1.24
Details
Luminosity	351 L☉
Other designations
	CPD–73° 1625, HD 138800, HIP 76750, HR 5782, SAO 257307.
Database references
SIMBAD	data

Kappa² Apodis (κ² Apodis) is the Bayer designation for a double star in the southern circumpolar constellation of Apus. It is located at a distance of roughly 780 light-years (240 parsecs) from Earth, based upon parallax measurements with a 7% margin of error. The pair have a combined apparent visual magnitude of +5.65,^[2] which makes the system faintly visible to the naked eye.

The brighter star has a stellar classification of B7 III-IV, with the luminosity class of III-IV suggesting that it may lie in an intermediate stage between a subgiant and a giant star.^[7] The faint companion is a K-type main sequence star with a classification of K0 V. It has a visual magnitude of 12.5 and an angular separation of 15 arcseconds from the brighter member.^[3]

References

^ ^a ^b ^c ^d ^e van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
^ ^a ^b ^c ^d Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
^ ^a ^b Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
^ Wilson, Ralph Elmer (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication, Washington: Carnegie Institution of Washington, Bibcode:1953GCRV..C......0W.
^ ^a ^b Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
^ "HR 5782 -- Star in double system", SIMBAD Astronomical Object Database, Centre de Données astronomiques de Strasbourg, retrieved 2012-07-10.
^ Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1975mcts.book.....H.