Astronomy:9 Lacertae

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Short description: Star in the constellation Lacerta
9 Lacertae
Location of 9 Lacertae (circled in red)
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[3]
Spectral type A9VkA7mA6[4]
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
Mass1.71[5] M
Radius3.28[5] R
Luminosity30[5] L
Surface gravity (log g)3.64[5] cgs
Temperature7,464[5] K
Metallicity [Fe/H]−0.20[6] dex
Rotational velocity (v sin i)105[3] km/s
Age513[7] 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.[4] 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[7] million years old with a high projected rotational velocity of 105 km/s.[3] The star has 1.7 times the mass of the Sun and about 3.3 times the Sun's radius. It is radiating 30 times the Sun's luminosity from its photosphere at an effective temperature of 7464 K.[5]

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 3.2 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. 
  4. 4.0 4.1 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. 
  5. 5.0 5.1 5.2 5.3 5.4 5.5 Stassun, Keivan G. et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal 158 (4): 138. doi:10.3847/1538-3881/ab3467. Bibcode2019AJ....158..138S. 
  6. 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. 
  7. 7.0 7.1 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. 
  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.