Kappa Doradus

κ Doradus
Location of κ Doradus on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Dorado
Right ascension 04h 44m 21.17834s[1]
Declination −59° 43′ 57.8563″[1]
Apparent magnitude (V) 5.28[2] (5.27 - 5.30)[3]
Characteristics
Spectral type A8 IV[4]
B−V color index +0.20[5]
Variable type suspected δ Scuti[3]
Astrometry
Radial velocity (Rv)0.00±3.70[6] km/s
Proper motion (μ) RA: +23.860 mas/yr[1]
Dec.: +39.974 mas/yr[1]
Parallax (π)14.8207 ± 0.0795 mas[1]
Distance220 ± 1 ly
(67.5 ± 0.4 pc)
Absolute magnitude (MV)+1.15[7]
Details
Mass1.78+0.36
−0.20[8] M☉
Radius2.88+0.21
−0.19[9] R☉
Luminosity26.6[10] L☉
Surface gravity (log g)3.79±0.08[9] cgs
Temperature7,623±123[11] K
Metallicity [Fe/H]−0.18[12] dex
Rotational velocity (v sin i)230[13] km/s
Other designations
κ Dor, 12 G. Doradus[14], NSV 16162, CPD−59°376, FK5 2354, GC 5810, HD 30478, HIP 22040, HR 1530, SAO 233664, TIC 220414802[15]
Database references
SIMBADdata

Kappa Doradus, Latinized from κ Doradus, is a solitary star[16] located in the southern constellation Dorado. It is faintly visible to the naked eye as a white-hued point of light with an apparent magnitude of 5.28.[2] The object is located relatively close at a distance of 220 light-years based on Gaia DR3 parallax measurements[1] and its distance from the Solar System is not changing, having a somewhat constrained heliocentric radial velocity of 0.00 km/s.[6] At its current distance, Kappa Doradus' brightness is diminished by two-tenths of a magnitude due to interstellar extinction[17] and it has an absolute magnitude of +1.15.[7]

The object has been given many different classes. Houk & Cowley (1975) gave a class of A8/9 III/IV,[18] indicating that it is an evolved A-type star with the characteristics of an A8 and A9 star and the blended luminosity class of a giant star and a subgiant. It has also been given a class of A8 IV and A5 III,[4][19] indicating either a slightly evolved subgiant or an evolved giant star. Kappa Doradus has 1.78 times the mass of the Sun[8] and 2.88 times the radius of the Sun.[9] However, this is only its polar radius, as it has an equatorial bulge 26% greater than its polar radius.[20] It radiates 26.6 times the luminosity of the Sun[10] from its photosphere at an effective temperature of 7,623 K.[11] Kappa Doradus is metal deficient with an iron abundance 66.1% of the Sun's or [Fe/H] = −0.18.[12] Like many hot stars it spins rapidly, having a projected rotational velocity of 230 km/s,[13] which causes the aforementioned oblation.[20]

Kappa Doradus variability was first observed in 1981 by astronomer H. M. Matizen.[21] In the paper, it is used as a comparison star for Alpha Doradus. Matizen found out that Kappa Doradus show Delta Scuti-like amplitudes of 0.03 magnitudes in the visual passband within hours.[3] As of 2004 however, it has not been confirmed to be variable.[22]

  1. ^ a b c d e Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Tycho2000 was invoked but never defined (see the help page).
  3. ^ a b c Cite error: The named reference Samus2017 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Gray1989 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Lake1965 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Kharchenko2007 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  9. ^ a b c Cite error: The named reference AP1999 was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference McDonald2012 was invoked but never defined (see the help page).
  11. ^ a b Cite error: The named reference Paunzen2006 was invoked but never defined (see the help page).
  12. ^ a b Cite error: The named reference Anders2019 was invoked but never defined (see the help page).
  13. ^ a b Cite error: The named reference Huang1953 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Gould1879 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  16. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  17. ^ Cite error: The named reference Gontcharov2017 was invoked but never defined (see the help page).
  18. ^ Cite error: The named reference Houk1975 was invoked but never defined (see the help page).
  19. ^ Cite error: The named reference Abt1995 was invoked but never defined (see the help page).
  20. ^ a b Cite error: The named reference van Belle2012 was invoked but never defined (see the help page).
  21. ^ Cite error: The named reference Maitzen1981 was invoked but never defined (see the help page).
  22. ^ Cite error: The named reference Samus2004 was invoked but never defined (see the help page).