Gamma Hydri

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γ Hydri
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Hydrus
Right ascension 03h 47m 14.34s[1]
Declination −74° 14′ 20.3″[1]
Apparent magnitude (V) 3.26[2]
Absolute magnitude (V) −0.83[3]
Spectral type M2III[4]
Other designations
CD–74° 276, HD 24512, HIP 17678, HR 1208, SAO 256029

γ Hydri, Latinised as Gamma Hydri, is a star in the constellation Hydrus. Located around 65.61 parsecs (214.0 ly) distant,[1] it is a red giant of spectral type M2III,[4] a star that has used up its core hydrogen and has expanded. A semiregular variable, it pulsates between magnitudes 3.26 and 3.33, although its period is not yet known precisely.[5]


  1. ^ a b c 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. ^ Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237: 0. Bibcode:2002yCat.2237....0D. 
  3. ^ Cardini, D. (January 2005), "Mg II chromospheric radiative loss rates in cool active and quiet stars", Astronomy and Astrophysics, 430: 303−311, Bibcode:2005A&A...430..303C, doi:10.1051/0004-6361:20041440. 
  4. ^ a b "Gamma Hydri". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 12 July 2015. 
  5. ^ Tabur, V.; Bedding, T. R.; Kiss, L. L.; Moon, T. T.; Szeidl, B.; Kjeldsen, H. (2009). "Long-term Photometry and Periods for 261 Nearby Pulsating M Giants". Monthly Notices of the Royal Astronomical Society. 400 (4): 1945–61. Bibcode:2009MNRAS.400.1945T. arXiv:0908.3228Freely accessible. doi:10.1111/j.1365-2966.2009.15588.x.