Astronomy:9 Lacertae

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Short description: Star in the constellation Lacerta
9 Lacertae
Observation data
Equinox J2000.0]] (ICRS)
Constellation Lacerta
Right ascension  22h 37m 22.41727s[1]
Declination +51° 32′ 42.4383″[1]
Apparent magnitude (V) 4.64[2]
Characteristics
Evolutionary stage main sequence
Spectral type A9VkA7mA6[3]
B−V color index 0.254±0.006[2]
Astrometry
Radial velocity (Rv)+10.1±1.5[2] km/s
Proper motion (μ) RA: −51.83[1] mas/yr
Dec.: −103.80[1] mas/yr
Parallax (π)19.00 ± 0.19[1] mas
Distance172 ± 2 ly
(52.6 ± 0.5 pc)
Absolute magnitude (MV)1.03[2]
Details
Mass1.59[4] M
Radius2.1[5] R
Luminosity34.6+0.9
−1.0
[6] L
Surface gravity (log g)3.77±0.14[4] cgs
Temperature7,614±259[4] K
Metallicity [Fe/H]−0.20[7] dex
Rotational velocity (v sin i)105[6] km/s
Age513[4] Myr
Other designations
9 Lac, BD+50° 3770, HD 214454, HIP 111674, HR 8613, SAO 34628[8]
Database references
SIMBADdata

9 Lacertae is a single[9] star in the northern constellation Lacerta, located 172 light years away from Sun.[1] It is visible to the naked eye as a faint, white-hued star with an apparent visual magnitude of 4.64.[2] This object is moving further from the Earth with a heliocentric radial velocity of +10 km/s.[2]

This is an A-type main-sequence star with a stellar classification of A9VkA7mA6.[3] This notation indicates it has the Hydrogen lines of an A9 star, the Calcium K line of an A7 star, and the metal lines of an A6. It is 513[4] million years old with a high projected rotational velocity of 105 km/s.[6] The star has 1.59[4] times the mass of the Sun and about 2.1[5] times the Sun's radius. It is radiating 34.6[6] times the Sun's luminosity from its photosphere at an effective temperature of 7,614 K.[4]

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. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 Gray, R. O. et al. (2001), "The Physical Basis of Luminosity Classification in the Late A-, F-, and Early G-Type Stars. I. Precise Spectral Types for 372 Stars", The Astronomical Journal 121 (4): 2148, doi:10.1086/319956, Bibcode2001AJ....121.2148G. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 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, doi:10.1088/0004-637X/804/2/146, Bibcode2015ApJ...804..146D. 
  5. 5.0 5.1 Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367: 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P. 
  6. 6.0 6.1 6.2 6.3 Zorec, J. et al. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, Bibcode2012A&A...537A.120Z. 
  7. Erspamer, D.; North, P. (February 2003), "Automated spectroscopic abundances of A and F-type stars using echelle spectrographs. II. Abundances of 140 A-F stars from ELODIE", Astronomy and Astrophysics 398 (3): 1121–1135, doi:10.1051/0004-6361:20021711, Bibcode2003A&A...398.1121E. 
  8. "9 Lac". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=9+Lac. 
  9. Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E.