Lambda Geminorum

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Lambda Geminorum
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Gemini
Right ascension 07h 18m 05.57977s[1]
Declination +16° 32′ 25.3905″[1]
Apparent magnitude (V) 3.571[2]
Characteristics
Spectral type A3V[3]
U−B color index +0.167[2]
B−V color index +0.113[2]
Variable type CST[4]
Astrometry
Radial velocity (Rv) –7.40[5] km/s
Proper motion (μ) RA: –44.43[1] mas/yr
Dec.: –36.61[1] mas/yr
Parallax (π) 32.33 ± 0.20[1] mas
Distance 100.9 ± 0.6 ly
(30.9 ± 0.2 pc)
Details
Mass 2.098[3] M
Radius 2.7773 ± 0.0469[3] R
Luminosity 27.3901 ± 0.3416[3] L
Temperature 7,932 ± 62[3] K
Rotational velocity (v sin i) 154[6] km/s
Age 0.8[3] Gyr
Other designations
54 Geminorum, BD+16 1443, FK5 277, HD 56537, HR 2763, HIP 35350, NSV 3512, SAO 96746.[7]
Database references
SIMBAD data

Lambda Geminorum (λ Gem, λ Geminorum) is a class A3, fourth-magnitude star in the constellation Gemini. Lambda Geminorum was a suspected variable star, but is now confirmed as constant,[4] located about 101 light-years from Earth. It has 2.8 times the radius of the Sun and is radiating 27 times the Sun's luminosity. It has 2.1 times the mass of the Sun and is around 800 million years old.[3]

References[edit]

  1. ^ a b c d e van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, Bibcode:2007A&A...474..653V, arXiv:0708.1752Freely accessible, doi:10.1051/0004-6361:20078357. 
  2. ^ a b c Gutierrez-Moreno, Adelina; et al. (1966), A System of photometric standards, 1, Publicaciones Universidad de Chile, Department de Astronomy, pp. 1–17, Bibcode:1966PDAUC...1....1G. 
  3. ^ a b c d e f g Boyajian, Tabetha S.; et al. (July 2013), "Stellar Diameters and Temperatures. III. Main-sequence A, F, G, and K Stars: Additional High-precision Measurements and Empirical Relations", The Astrophysical Journal, 771 (1): 40, Bibcode:2013ApJ...771...40B, arXiv:1306.2974Freely accessible, doi:10.1088/0004-637X/771/1/40. 
  4. ^ a b "Lam Gem". The International Variable Star Index. AAVSO – American Association of Variable Star Observers. Retrieved March 29, 2017. 
  5. ^ 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, Bibcode:2006AstL...32..759G, doi:10.1134/S1063773706110065. 
  6. ^ Royer, F.; et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics, 463 (2): 671–682, Bibcode:2007A&A...463..671R, arXiv:astro-ph/0610785Freely accessible, doi:10.1051/0004-6361:20065224. 
  7. ^ "HD 56537 -- Variable Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2006-12-09