HD 24479, also designated as HR 1204, is a solitary,[1] bluish-white hued star located in the northern circumpolar constellation Camelopardalis. The star is visible to the naked eye with an apparent visual magnitude of 5.04.[2] Based on Gaia DR3 parallax measurements,[3] it is located 385 light years from the Sun. However, it is receding with a somewhat constrained heliocentric radial velocity of 4.6 km/s.[4] At its current distance, HD 24479's brightness is diminished by 0.29 magnitudes due to interstellar dust.[5]

In 1932, HD 24479 was identified as a Be star by Olin C. Wilson at the Mount Wilson Observatory.[6] In 1969, astronomer Anne Cowley and her colleagues listed a stellar classification of B9.5 V,[7] matching a B-type main-sequence star. Slettebak (1982) gave it a class of B9 IV,[8] suggesting this instead an evolving subgiant star. Zorec and Royer (2012) model it to be an evolved dwarf star that has completed 85.9% of its main sequence lifetime.[9]

It has an estimated 3.14 times the mass of the Sun[9] and 4.1 times the Sun's radius,[10] which is large for its class. The star is radiating 156 times the Sun's luminosity[10] from its photosphere at an effective temperature of 10,250 K.[9] HD 24479 is estimated to be 256 million years old[11] and is spinning quickly with a projected rotational velocity of 85 km/s.[12]

References

  1. ^ Eggleton, P. P. & Tokovinin, A. A. (11 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. ISSN 0035-8711
  2. ^ Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system.". VizieR Online Data Catalog. 2237. Bibcode:2002yCat.2237....0D
  3. ^
  4. ^ Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. ISSN 1063-7737. S2CID 119231169
  5. ^ Gontcharov, George A. & Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. ISSN 0035-8711
  6. ^ Wilson, Olin C. Jr. (April 1932). "Three New Be Stars". Publications of the Astronomical Society of the Pacific. 44 (258): 124. Bibcode:1932PASP...44..124W. doi:10.1086/124211. ISSN 0004-6280
  7. ^ Cowley, A.; Cowley, C.; Jaschek, M.; Jaschek, C. (April 1969). "A study of the bright stars. I. A catalogue of spectral classifications.". The Astronomical Journal. 74: 375. Bibcode:1969AJ.....74..375C. doi:10.1086/110819. ISSN 0004-6256
  8. ^ Slettebak, A. (September 1982). "Spectral types and rotational velocities of the brighter Be stars and A-F type shell stars". The Astrophysical Journal Supplement Series. 50: 55. Bibcode:1982ApJS...50...55S. doi:10.1086/190820. ISSN 0067-0049
  9. ^ Zorec, J. & Royer, F. (January 2012). "Rotational velocities of A-type stars IV: Evolution of rotational velocities". Astronomy & Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691. ISSN 0004-6361. S2CID 55586789
  10. ^ Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants". Astronomy & Astrophysics. 426 (1): 297–307. arXiv:astro-ph/0404180. Bibcode:2004A&A...426..297K. doi:10.1051/0004-6361:20035930. ISSN 0004-6361
  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. ISSN 1063-7737. S2CID 255202762
  12. ^ Abt, Helmut A.; Levato, Hugo; Grosso, Monica (July 2002). "Rotational Velocities of B Stars". The Astrophysical Journal. 573 (1): 359–365. Bibcode:1982ApJS...50...55S. doi:10.1086/340590. ISSN 0004-637X