Astronomy:Lambda Persei

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Short description: Star in the constellation Perseus
Lambda Persei
Perseus constellation map.svg
Red circle.svg
Location of λ Persei (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Perseus
Right ascension  04h 06m 35.04360s[1]
Declination 50° 21′ 04.5500″[1]
Apparent magnitude (V) 4.29[2]
Characteristics
Spectral type A0IVn[3]
U−B color index −0.04[2]
B−V color index +0.02[2]
Astrometry
Radial velocity (Rv)+6.1±2.0[4] km/s
Proper motion (μ) RA: −12.75[1] mas/yr
Dec.: −35.60[1] mas/yr
Parallax (π)7.73 ± 0.22[1] mas
Distance420 ± 10 ly
(129 ± 4 pc)
Absolute magnitude (MV)−1.31[5]
Details
Radius3.1[6] R
Luminosity348[5] L
Surface gravity (log g)4.05[7] cgs
Temperature10,585[7] K
Metallicity [Fe/H]+0.01[7] dex
Rotational velocity (v sin i)196[8] km/s
Age345[9] Myr
Other designations
λ Per, 47 Persei, BD+49°1101, FK5 1113, GC 4924, HD 25642, HIP 19167, HR 1261, SAO 24412[10]
Database references
SIMBADdata

λ Persei, Latinized as Lambda Persei, is a star in the northern constellation of Perseus. It is visible to the naked eye as a faint, white-hued point of light with an apparent visual magnitude of 4.29.[2] This object is located approximately 422 light years from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +6 km/s.[4]

λ Persei in optical light

This object has a stellar classification of A0IVn,[3] matching an A-type subgiant star with "nebulous" lines due to rapid rotation. It is spinning with a projected rotational velocity of 196 km/s,[8] which is giving the star an equatorial bulge that is an estimated 16% larger than the polar radius.[11] Unusually for a star of this type, spectra show weak emission features among the Hydrogen lines, which may be due to plage regions on the surface caused by an implied magnetic field.[12] The star is 345[9] million years old and is radiating 348[5] times the luminosity of the Sun from its photosphere at an effective temperature of 10,585 K.[7]

In Chinese astronomy, Lambda Persei is called 積水, Pinyin: Jīshuǐ, meaning Stored Water, because this star is marking itself and stand alone in Stored Water asterism, Stomach mansion (see : Chinese constellation).[13]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V.  Vizier catalog entry
  2. 2.0 2.1 2.2 2.3 Ducati, J. R. (2002). "Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues 2237. Bibcode2002yCat.2237....0D. 
  3. 3.0 3.1 Cowley, A. et al. (April 1969). "A study of the bright A stars. I. A catalogue of spectral classifications". Astronomical Journal 74: 375–406. doi:10.1086/110819. Bibcode1969AJ.....74..375C. 
  4. 4.0 4.1 Wilson, R. E. (1953). General Catalogue of Stellar Radial Velocities. Carnegie Institution for Science. Bibcode1953GCRV..C......0W. 
  5. 5.0 5.1 5.2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A.  Vizier catalog entry
  6. Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367 (2): 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P 
  7. 7.0 7.1 7.2 7.3 Wu, Yue et al. (2010). "Coudé-feed stellar spectral library – atmospheric parameters". Astronomy & Astrophysics 525: A71. doi:10.1051/0004-6361/201015014. Bibcode2011A&A...525A..71W. 
  8. 8.0 8.1 Hoffleit, D.; Warren, W. H. (1995). "Bright Star Catalogue". VizieR On-line Data Catalog: V/50. Originally Published in: 1964BS....C......0H 5050. Bibcode1995yCat.5050....0H. 
  9. 9.0 9.1 Gontcharov, G. A. (November 2012). "Spatial distribution and kinematics of OB stars". Astronomy Letters 38 (11): 694–706. doi:10.1134/S1063773712110035. Bibcode2012AstL...38..694G. 
  10. "lam Per". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=lam+Per. 
  11. Belle, G. T. (2012). "Interferometric observations of rapidly rotating stars". The Astronomy and Astrophysics Review 20: 51. doi:10.1007/s00159-012-0051-2. Bibcode2012A&ARv..20...51V. 
  12. Underhill, Anne B. (November 1991). "Lambda Persei: an Unusual B9 IV Star". Publications of the Astronomical Society of the Pacific 103: 1176. doi:10.1086/132937. Bibcode1991PASP..103.1176U. 
  13. (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日