Lambda Capricorni

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Lambda Capricorni
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Capricornus
Right ascension  21h 46m 32.09739s[1]
Declination −11° 21′ 57.4391″[1]
Apparent magnitude (V) +5.56[2]
Spectral type A1 V[3]
B−V color index −0.01[2]
Radial velocity (Rv)−2.4[4] km/s
Proper motion (μ) RA: +28.92[1] mas/yr
Dec.: −9.66[1] mas/yr
Parallax (π)11.58 ± 0.30[1] mas
Distance282 ± 7 ly
(86 ± 2 pc)
Absolute magnitude (MV)+0.89[5]
Mass2.50[6] M
Radius2.2[7] R
Luminosity45[5] L
Surface gravity (log g)4.15±0.14[6] cgs
Temperature10,674±363[6] K
Rotational velocity (v sin i)192.5±5.7[8] km/s
Age155[6] Myr
Other designations
λ Cap, 48 Cap, BD−12° 6087, FK5 818, HD 207052, HIP 107517, HR 8319, SAO 164639[9]
Database references

Lambda Capricorni, Latinized from λ Capricorni, is a solitary[10] star in the southern constellation of Capricornus. It is faintly visible to the naked eye with an apparent visual magnitude of +5.56.[2] Based upon an annual parallax shift of 11.58 mas as seen from the Earth,[1] the star is located about 282 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.11 due to interstellar dust.[11]

This is a white-hued A-type main sequence star with a stellar classification of A1 V,[3] it is a magnetic Ap star, indicating the spectrum displays chemically peculiar features.[8] The star has an estimated 2.50[6] times the mass of the Sun and about 2.2[7] times the Sun's radius. It is 155[6] million years old and is spinning rapidly with a projected rotational velocity of 192.5 km/s.[8] Lambda Capricorni is radiating 45[5] times the Sun's luminosity from its photosphere at an effective temperature of 10,674 K.[6]


  1. ^ a b c d e f van Leeuwen, F. (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 Corben, P. M.; Stoy, R. H. (1968), "Photoelectric Magnitudes and Colours for Bright Southern Stars", Monthly Notes of the Astronomical Society of Southern Africa, 27: 11, Bibcode:1968MNSSA..27...11C.
  3. ^ a b Royer, F.; et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224.
  4. ^ Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system", Astronomy Letters, 32 (11): 759–771, arXiv:1606.08053, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065.
  5. ^ a b c 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.
  6. ^ a b c d e f g David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146.
  7. ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics (3rd ed.), 367: 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451.
  8. ^ a b c Wraight, K. T.; et al. (February 2012), "A photometric study of chemically peculiar stars with the STEREO satellites - I. Magnetic chemically peculiar stars", Monthly Notices of the Royal Astronomical Society, 420 (1): 757–772, arXiv:1110.6283, Bibcode:2012MNRAS.420..757W, doi:10.1111/j.1365-2966.2011.20090.x.
  9. ^ "lam Cap". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-05-13.
  10. ^ 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.
  11. ^ Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv:1606.09028, Bibcode:2012AstL...38..694G, doi:10.1134/S1063773712110035.