HD 4628

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HD 4628
Observation data
Epoch J2000      Equinox J2000
Constellation Pisces
Right ascension 00h 48m 22.98s[1]
Declination +05° 16′ 50.2″[1]
Apparent magnitude (V) 5.75
Spectral type K2.5 V[2]
U−B color index 0.59
B−V color index 0.89
Variable type None
Radial velocity (Rv) -12.6 km/s
Proper motion (μ) RA: 757.11 ± 0.48[1] mas/yr
Dec.: -1,141.33 ± 0.34[1] mas/yr
Parallax (π) 134.14 ± 0.51[1] mas
Distance 24.31 ± 0.09 ly
(7.45 ± 0.03 pc)
Absolute magnitude (MV) 5.88
Mass 0.70 ± 0.10[3] M
Radius 0.749 ± 0.051[4] R
Luminosity 0.28[3] L
Surface gravity (log g) 4.39 ± 0.16[3] cgs
Temperature 5,829 ± 41[3] K
Metallicity [Fe/H] –0.22[5] dex
Rotation 38.0 days[5]
Age 5.4[6] Gyr
Other designations
96 G. Piscium,[7] BD +04°123, GCTP 156.00, Gl 33, HD 4628, HIP 3765, HR 222, LHS 121, LTT 10285, SAO 109471, Wolf 25.

HD 4628 (96 G. Piscium) is a main sequence dwarf star in the constellation Pisces. It has a spectral classification of K2, giving it an orange-red hue and a slightly smaller mass and girth than our Sun. It lies at a distance of approximately 24 light years from us and has a relatively high proper motion.[1] The apparent magnitude is just sufficient for this star to be viewed with the unaided eye. The star appears to be slightly older than our Sun—approximately 5.4 billion years old.[6]

No definitive companion has yet been found in orbit around this star. In 1958 it was thought to have stellar companion that was also a flare star, but this was subsequently disproved.[8]


  1. ^ a b c d e f van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.  Vizier catalog entry
  2. ^ Gray, R. O. et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample", The Astronomical Journal 132 (1): 161–170, arXiv:astro-ph/0603770, Bibcode:2006AJ....132..161G, doi:10.1086/504637 
  3. ^ a b c d Ghezzi, L. et al. (September 2010), "Stellar Parameters and Metallicities of Stars Hosting Jovian and Neptunian Mass Planets: A Possible Dependence of Planetary Mass on Metallicity", The Astrophysical Journal 720 (2): 1290–1302, arXiv:1007.2681, Bibcode:2010ApJ...720.1290G, doi:10.1088/0004-637X/720/2/1290 
  4. ^ van Belle, Gerard T.; von Braun, Kaspar (2009). "Directly Determined Linear Radii and Effective Temperatures of Exoplanet Host Stars". The Astrophysical Journal 694 (2): 1085–1098. arXiv:0901.1206. Bibcode:2009ApJ...694.1085V. doi:10.1088/0004-637X/694/2/1085. 
  5. ^ a b Maldonado, J. et al. (October 2010), "A spectroscopy study of nearby late-type stars, possible members of stellar kinematic groups", Astronomy and Astrophysics 521: A12, arXiv:1007.1132, Bibcode:2010A&A...521A..12M, doi:10.1051/0004-6361/201014948 
  6. ^ a b 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 
  7. ^ Gould, B. A., Uranometria Argentina, Reprinted and updated by Pilcher, F, retrieved 2010-07-16 
  8. ^ Hartkopf & McAlister, 1984, "Binary stars unresolved by speckle interferometry", Astronomical Society of the Pacific, vol. 96.

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