HD 17925

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HD 17925
Observation data
Epoch J2000      Equinox J2000
Constellation Eridanus
Right ascension 02h 52m 32.12836s[1]
Declination –12° 46′ 10.9692″[1]
Apparent magnitude (V) 6.04[2]
Spectral type K1V[3]
U−B color index +0.55[2]
B−V color index +0.87[2]
Variable type BY Dra[4]
Radial velocity (Rv) +17.77±0.08[5] km/s
Proper motion (μ) RA: 397.41±0.45[1] mas/yr
Dec.: −189.32±0.36[1] mas/yr
Parallax (π) 96.60 ± 0.40[1] mas
Distance 33.8 ± 0.1 ly
(10.35 ± 0.04 pc)
Absolute magnitude (MV) 5.97[6]
Temperature 5225 ± 5.0[7] K
Metallicity [Fe/H] +0.10[8] dex
Rotation 6.6 days[8]
Rotational velocity (v sin i) 4.80[9] km/s
Age 100[10] Myr
Other designations
32 G. Eridani, EP Eri, BD-13°544, GJ 117, HIP 13402, HR 857, SAO 148647, YPC 599.
Database references

HD 17925 (32 G. Eridani) is a solitary K-type main sequence star located 34 light-years away, in the constellation Eridanus. It is a likely member of the Local Association of nearby, co-moving stars.[8] The spectrum shows a strong abundance of lithium, indicating that it is young star. This likely makes its point of origin the nearby Scorpio–Centaurus Complex.[11] It is a BY Draconis variable showing a rotational modulation with a period of 1.75 days, and has been observed to flare.[4]

An infrared excess has been detected around this star, most likely indicating the presence of a circumstellar disk at a radius of 17.9 AU. The temperature of this dust is 52 K.[12]


  1. ^ a b c d e van Leeuwen, F. (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.  Vizier catalog entry
  2. ^ a b c Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV data. SIMBAD, Bibcode:1986EgUBV........0M. 
  3. ^ Montes, D.; et al. (2001), "Late-type members of young stellar kinematic groups - I. Single stars", Monthly Notices of the Royal Astronomical Society, 328 (1): 45–63, Bibcode:2001MNRAS.328...45M, arXiv:astro-ph/0106537Freely accessible, doi:10.1046/j.1365-8711.2001.04781.x. 
  4. ^ a b Abbott, B. P.; Pomerance, B. H.; Ambruster, C. W. (March 1995), "UBVRI Photometry of the Solar Neighborhood Pleiades-Age K Dwarfs HD 17925 and HD 1405", Bulletin of the American Astronomical Society, 27: 842, Bibcode:1995AAS...186.2210A. 
  5. ^ Karataş, Y.; et al. (April 2004), "Kinematics of chromospherically active binaries and evidence of an orbital period decrease in binary evolution", Monthly Notices of the Royal Astronomical Society, 349 (3): 1069–1092, Bibcode:2004MNRAS.349.1069K, arXiv:astro-ph/0404219Freely accessible, doi:10.1111/j.1365-2966.2004.07588.x. 
  6. ^ Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, Bibcode:2009A&A...501..941H, arXiv:0811.3982Freely accessible, doi:10.1051/0004-6361/200811191. 
  7. ^ Kovtyukh, V. V.; et al. (2003), "High precision effective temperatures for 181 F-K dwarfs from line-depth ratios", Astronomy and Astrophysics, 411 (3): 559–564, Bibcode:2003A&A...411..559K, arXiv:astro-ph/0308429Freely accessible, doi:10.1051/0004-6361:20031378. 
  8. ^ a b c 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, Bibcode:2010A&A...521A..12M, arXiv:1007.1132Freely accessible, doi:10.1051/0004-6361/201014948. 
  9. ^ Mishenina, T. V.; et al. (November 2012), "Activity and the Li abundances in the FGK dwarfs", Astronomy & Astrophysics, 547: 8, Bibcode:2012A&A...547A.106M, arXiv:1210.6843Freely accessible, doi:10.1051/0004-6361/201118412, A106. 
  10. ^ 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, Bibcode:2008ApJ...687.1264M, arXiv:0807.1686Freely accessible, doi:10.1086/591785. 
  11. ^ Cayrel de Strobel, G.; Cayrel, R. (July 1989), "Strong lithium in the very nearby K-dwarf HD 17925", Astronomy and Astrophysics, 218 (1–2): L9–L12, Bibcode:1989A&A...218L...9C 
  12. ^ Eiroa, C.; et al. (July 2013), "DUst around NEarby Stars. The survey observational results", Astronomy & Astrophysics, 555: A11, Bibcode:2013A&A...555A..11E, arXiv:1305.0155Freely accessible, doi:10.1051/0004-6361/201321050. 

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