72 Herculis

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72 Herculis
Observation data
Epoch J2000      Equinox J2000
Constellation Hercules
Right ascension 17h 20m 39.567s
Declination +32° 28′ 03.88″
Apparent magnitude (V) 5.377 ± 0.005[1]
Characteristics
Spectral type G0 V
U−B color index 0.07
B−V color index 0.62
Variable type Suspected
Astrometry
Radial velocity (Rv) -78.7 km/s
Proper motion (μ) RA: 135.41 mas/yr
Dec.: -1040.65 mas/yr
Parallax (π) 69.48 ± 0.56 mas
Distance 46.9 ± 0.4 ly
(14.4 ± 0.1 pc)
Absolute magnitude (MV) 4.43 ± 0.05[1]
Details
Mass 0.91[1] M
Radius 1.17 ± 0.04[1] R
Surface gravity (log g) 4.26 ± 0.10[1] cgs
Temperature 5,625[2] K
Metallicity [Fe/H] -0.60[2] dex
Rotational velocity (v sin i) 1.0 ± 1.0[1] km/s
Age 4.1–6.6[3] Gyr
Other designations
72 Her, w Her, BD +32°2896, FK5 1456, GCTP 3946, GJ 672, HD 157214, HIP 84862, HR 6458, LHS 441, LTT 15148, SAO 65963, NSV 8553.

72 Herculis is a main sequence dwarf star in the constellation Hercules. The Flamsteed designation for this star comes from the publication Historia Coelestis Britannica by John Flamsteed. It is the 72nd star in Flamsteed's list of stars in Hercules.

Based on its spectral classification of G0 V, it is similar in mass and luminosity to the Sun. Parallax measurements show this star to be about 47 light years from the solar system. The photosphere shows an effective temperature of 5,625 °K[2] and a metallicity (Fe/H) equal to -0.60 ± 0.20.[2]

The Washington Visual Double Star Catalog for 1996 showed two visual companions of this star. The first is a visual magnitude 9.7 star located 289.1 arc seconds away. The second is only separated by 8.7 arc seconds, and is magnitude 12.9.[4] It is unknown whether these visual companions are gravitationally-bound to 72 Her.

References[edit]

  1. ^ a b c d e f Fuhrmann, Klaus (February 2008), "Nearby stars of the Galactic disc and halo - IV", Monthly Notices of the Royal Astronomical Society 384 (1): 173–224, Bibcode:2008MNRAS.384..173F, doi:10.1111/j.1365-2966.2007.12671.x 
  2. ^ a b c d G. Israelian, R.J.L. García, R. Rebolo (1998). "Oxygen Abundances in Unevolved Metal-poor Stars from Near-Ultraviolet OH Lines". The Astrophysical Journal 507 (2): 805–817. arXiv:astro-ph/9806235. Bibcode:1998ApJ...507..805I. doi:10.1086/306351. Retrieved 2006-08-17. 
  3. ^ Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008). "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics". The Astrophysical Journal 687 (2): 1264–1293. arXiv:0807.1686. Bibcode:2008ApJ...687.1264M. doi:10.1086/591785. 
  4. ^ C.E. Worley, G.G. Douglass (1997). "The Washington Visual Double Star Catalog" (abstract page). Astronomy & Astrophysics Supplement Series 125. 

External links[edit]