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Gamma Reticuli
Diagram showing star positions and boundaries of the Reticulum constellation and its surroundings
Location of γ Reticuli (circled)
Observation data
Epoch J2000.0       Equinox J2000.0 ( ICRS)
Constellation Reticulum
Right ascension 04h 00m 53.80860s [1]
Declination −62° 09′ 33.4250″ [1]
Apparent magnitude (V) 4.5 [2]
Characteristics
Evolutionary stage asymptotic giant branch [3]
Spectral type M4 III [4]
U−B color index +1.81 [2]
B−V color index +1.66 [2]
Variable type SR [5]
Astrometry
Radial velocity (Rv)−7.0±2.7 [6] km/s
Proper motion (μ) RA: +3.03 [1]  mas/ yr
Dec.: +34.67 [1]  mas/ yr
Parallax (π)6.95 ± 0.11  mas [1]
Distance469 ± 7  ly
(144 ± 2  pc)
Absolute magnitude (MV)−1.31 [7]
Details
Mass1.5−2 [5]  M☉
Radius115 [5]  R☉
Luminosity1,846 [8]  L☉
Surface gravity (log g)0.8 [5]  cgs
Temperature3,599 [8]  K
Metallicity [Fe/H]0.0 [5]  dex
Other designations
γ Ret, CD−62° 149, HD 25705, HIP 18744, HR 1264, SAO 248925. [9]
Database references
SIMBAD data

Gamma Reticuli (Gamma Ret, γ Reticuli, γ Ret) is a solitary [10] star in the southern constellation of Reticulum. With an apparent visual magnitude of 4.5, [2] it can be faintly seen with the naked eye. Based upon an annual parallax shift of 6.95  mas, [1] it is located roughly 469  light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.08 due to interstellar dust. [5]

A light curve for Gamma Reticuli, plotted from Hipparcos data [11]

This is an evolved red giant star, currently on the asymptotic giant branch, [3] with a stellar classification of M4 III. [4] It is a semiregular variable with a period of 25 days. [5] Gamma Reticuli has 1.5−2 times the mass of the Sun, 115 times the Sun's radius, [5] and radiates 1,846 times the solar luminosity from its outer atmosphere at an effective temperature of 3,450 K. [8]

Gamma Reticuli is moving through the Galaxy at a speed of 24.8 km/s relative to the Sun. Its projected Galactic orbit carries it between 24,100 and 39,200 light years from the center of the Galaxy. [12]

References

  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, S2CID  18759600.
  2. ^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode: 1986EgUBV........0M.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. ^ a b Eggen, Olin J. (July 1992), "Asymptotic giant branch stars near the sun", Astronomical Journal, 104 (1): 275–313, Bibcode: 1992AJ....104..275E, doi: 10.1086/116239.
  4. ^ a b Houk, Nancy; Cowley, A. P. (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode: 1978mcts.book.....H.
  5. ^ a b c d e f g h Cruzalèbes, P.; et al. (September 2013), "Fundamental parameters of 16 late-type stars derived from their angular diameter measured with VLTI/AMBER", Monthly Notices of the Royal Astronomical Society, 434 (1): 437–450, arXiv: 1306.3288, Bibcode: 2013MNRAS.434..437C, doi: 10.1093/mnras/stt1037, S2CID  49573767.
  6. ^ de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv: 1208.3048, Bibcode: 2012A&A...546A..61D, doi: 10.1051/0004-6361/201219219, S2CID  59451347, A61.
  7. ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv: 1108.4971, Bibcode: 2012AstL...38..331A, doi: 10.1134/S1063773712050015, S2CID  119257644.
  8. ^ a b c McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv: 1208.2037, Bibcode: 2012MNRAS.427..343M, doi: 10.1111/j.1365-2966.2012.21873.x, S2CID  118665352.
  9. ^ "gam Ret". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-02-13.{{ cite web}}: CS1 maint: postscript ( link)
  10. ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv: 0806.2878, Bibcode: 2008MNRAS.389..869E, doi: 10.1111/j.1365-2966.2008.13596.x, S2CID  14878976.
  11. ^ "/ftp/cats/more/HIP/cdroms/cats". Centre de Données astronomiques de Strasbourg. Strasbourg astronomical Data Center. Retrieved 30 December 2022.
  12. ^ Gamma Reticuli (HIP 18744) Archived 2014-04-14 at the Wayback Machine
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