30 Camelopardalis (HD 38831; HR 2006), or simply 30 Cam, is a solitary star located in the northern circumpolar constellation Camelopardalis. It has an apparent magnitude of 6.13,[2] placing it near the limit for naked eye visibility, even under ideal conditions. Gaia DR3 parallax measurements imply a distance of 523 light-years[1] and it is currently drifting away with a somewhat constrained radial velocity of 12 km/s.[5] At its current distance, 30 Cam's brightness is diminished by an interstellar extinction of 0.18 magnitudes[13] and it has an absolute magnitude of +0.29.[6]
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Camelopardalis |
| Right ascension | 05h 52m 17.25442s[1] |
| Declination | +58° 57′ 50.7189″[1] |
| Apparent magnitude (V) | 6.13±0.01[2] |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | A0 Vs[3] |
| U−B color index | −0.14[4] |
| B−V color index | −0.04[4] |
| Astrometry | |
| Radial velocity (Rv) | 12±3.7[5] km/s |
| Proper motion (μ) | RA: −0.939 mas/yr[1] Dec.: −20.732 mas/yr[1] |
| Parallax (π) | 6.235 ± 0.0381 mas[1] |
| Distance | 523 ± 3 ly (160.4 ± 1.0 pc) |
| Absolute magnitude (MV) | +0.29[6] |
| Details | |
| Mass | 2.77+0.36 −0.44[7] M☉ |
| Radius | 3.20±0.16[8] R☉ |
| Luminosity | 107.9+1.4 −1.5[1] L☉ |
| Surface gravity (log g) | 3.87+0.09 −0.07[7] cgs |
| Temperature | 10,957[9] K |
| Metallicity [Fe/H] | 0.00[10] dex |
| Rotational velocity (v sin i) | 425:[11] km/s |
| Age | 294±40[1] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
30 Cam has a stellar classification of A0 Vs,[3] indicating that it is an A-type main-sequence star that is generating energy via hydrogen fusion at its core. In addition, the absorption lines in 30 Cam's spectrum are narrow and sharp, possibly due to slow rotation. It has 2.77 times the mass of the Sun[7] and 3.20 times the radius of the Sun.[8] It radiates 107.9 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 10,957 K,[9] giving it a bluish-white hue when viewed in the night sky. 30 Cam's ratio of its iron abundance to the amount of hydrogen is similar to the Sun's;[10] it is estimated to be 294 million years old.[1]
There have been many disagreements regarding the star's projected rotational velocity. Palmer et al. (1968) devised a velocity of 425 km/s,[11] the value being highly uncertain. This does not correlate with the spectral classification mentioned earlier. A 1974 focusing on bright hydrogen-emission stars stated that 30 Cam is indeed a slowly rotating star, but it does not give a value for its rotational velocity. [14]
References
edit- ^ a b c d e f g h i Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361. S2CID 17128864.
- ^ a b 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. S2CID 121555804.
- ^ a b Crawford, D. L. (1963). "U, b, v, and Hβ Photometry for the Bright B8- and B9-TYPE Stars". The Astrophysical Journal. 137. American Astronomical Society: 530. Bibcode:1963ApJ...137..530C. doi:10.1086/147526. ISSN 0004-637X.
- ^ a b Kharchenko, N.V.; Scholz, R.-D.; Piskunov, A.E.; Röser, S.; Schilbach, E. (November 2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten. 328 (9): 889–896. arXiv:0705.0878. Bibcode:2007AN....328..889K. doi:10.1002/asna.200710776. eISSN 1521-3994. ISSN 0004-6337. S2CID 119323941.
- ^ 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.
- ^ a b c Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.
- ^ a b Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (April 8, 2004). "The angular sizes of dwarf stars and subgiants: Surface brightness relations calibrated by interferometry". Astronomy & Astrophysics. 426 (1): 297–307. arXiv:astro-ph/0404180. Bibcode:2004A&A...426..297K. doi:10.1051/0004-6361:20035930. eISSN 1432-0746. ISSN 0004-6361. S2CID 6077801.
- ^ a b Philip, A. G. D.; Egret, D. (May 1980). "An analysis of the Hauck-Mermillod catalogue of homogeneous four-color data. II". Astronomy and Astrophysics Supplement Series. 40: 199–205. Bibcode:1980A&AS...40..199P. ISSN 0365-0138.
- ^ a b Gontcharov, G. A. (December 2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771–782. arXiv:1606.08814. Bibcode:2012AstL...38..771G. doi:10.1134/S1063773712120031. eISSN 1562-6873. ISSN 1063-7737. S2CID 118345778.
- ^ a b Palmer, D. R.; Walker, E. N.; Jones, D. H. P.; Wallis, R. E. (1968). "The radial velocities spectral types and projected rotational velocities of 633 bright northern A stars". Royal Greenwich Observatory Bulletins. 135: 385. Bibcode:1968RGOB..135..385P. S2CID 119068648.
- ^ "30 Cam". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-06-19.
- ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
- ^ Irvine, N. J. (March 1975), "New bright hydrogen-emission stars", Astrophysical Journal, 196: 773–775, Bibcode:1975ApJ...196..773I, doi:10.1086/153467.