Kappa2 Apodis

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For other star systems with this Bayer designation, see Kappa Apodis.
Kappa2 Apodis
Diagram showing star positions and boundaries of the Apus constellation and its surroundings
Cercle rouge 100%.svg

Location of κ2 Apodis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Apus
Right ascension 15h 40m 21.33360s[1]
Declination –73° 26′ 48.0648″[1]
Apparent magnitude (V) 5.65[2]
Characteristics
Spectral type B7 III-IV + K0 V[3]
U−B color index –0.38[2]
B−V color index –0.04[2]
Astrometry
Radial velocity (Rv) –19.0[4] km/s
Proper motion (μ) RA: –12.36[1] mas/yr
Dec.: –20.56[1] mas/yr
Parallax (π) 4.18 ± 0.28[1] mas
Distance 780 ± 50 ly
(240 ± 20 pc)
Other designations
CP–73 1625, HD 138800, HIP 76750, HR 5782, SAO 257307.[5]

Kappa2 Apodis2 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.[6] 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[edit]

  1. ^ 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. 
  2. ^ 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), Bibcode:1966CoLPL...4...99J. 
  3. ^ 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. 
  4. ^ Wilson, Ralph Elmer (1953), General Catalogue of Stellar Radial Velocities, Washington: Carnegie Institution of Washington, Bibcode:1953QB901.W495...... 
  5. ^ "HR 5782 -- Star in double system", SIMBAD Astronomical Object Database (Centre de Données astronomiques de Strasbourg), retrieved 2012-07-10. 
  6. ^ Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars 1, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1975mcts.book.....H. 

External links[edit]