Astronomy:Gamma Indi

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Short description: Star in the constellation Indus
Gamma Indi
Observation data
Equinox J2000.0]] (ICRS)
Constellation Indus[1]
Right ascension  21h 26m 15.43919s[2]
Declination −54° 39′ 37.6516″[2]
Apparent magnitude (V) 6.09±0.01[3]
Characteristics
Evolutionary stage main sequence[2][4]
Spectral type F1III[5]
Astrometry
Radial velocity (Rv)+10.4±0.6[6] km/s
Proper motion (μ) RA: +1.040[2] mas/yr
Dec.: +39.036[2] mas/yr
Parallax (π)15.1909 ± 0.0250[2] mas
Distance214.7 ± 0.4 ly
(65.8 ± 0.1 pc)
Absolute magnitude (MV)+1.98[1]
Details
Mass1.72[7] M
Radius2.47[8] R
Luminosity12.5[8] L
Surface gravity (log g)3.85[2] cgs
Temperature6,912[8] K
Metallicity [Fe/H]−0.09[7] dex
Age1.40[7] Gyr
Other designations
CPD−55°9586, HD 203760, HIP 105841, HR 8188, TYC 8810-1289-1[9]
Database references
SIMBADdata

Gamma Indi is a star in the constellation Indus. Its apparent magnitude is 6.09, much fainter than Delta Indi and unusually faint for a Gamma-labelled star, making it only visible from very dark skies in ideal conditions. Parallax measurements imply a distance of 65.8 parsecs (215 ly). The star is moving away with an heliocentric velocity of +10.4 km/s.

The spectrum of this star matches a spectral class of F1III,[5] with the luminosity class III suggesting it is a giant star that has exhausted the hydrogen at its core. However, stellar evolution models imply that it is not a giant star, but is still on the main sequence.[2] Around 1.72 times the mass of the Sun and 1.40 billion years old,[7] Gamma Indi is nearly 13 times as luminous as the Sun, with a radius 2.47 times larger. All this energy is released from its photosphere shining at an effective temperature of 6,912 K,[8] giving it the yellow-white hue typical of F-type stars.[10]

References

  1. 1.0 1.1 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A  XHIP record for this object at VizieR.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  3. Paunzen, E. (2015-08-01). "A new catalogue of Strömgren-Crawford uvbyβ photometry". Astronomy and Astrophysics 580: A23. doi:10.1051/0004-6361/201526413. ISSN 0004-6361. Bibcode2015A&A...580A..23P. 
  4. Chandler, Colin Orion; McDonald, Iain; Kane, Stephen R. (2016). "The Catalog of Earth-Like Exoplanet Survey Targets (CELESTA): A Database of Habitable Zones Around Nearby Stars". The Astronomical Journal 151 (3): 59. doi:10.3847/0004-6256/151/3/59. Bibcode2016AJ....151...59C. 
  5. 5.0 5.1 Malaroda, S. (August 1975). "Study of the F-type 1 MK spectral types." (in en). The Astronomical Journal 80: 637. doi:10.1086/111786. ISSN 0004-6256. 
  6. Gontcharov, G. A. (2006-11-01). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system" (in en). Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. ISSN 1562-6873. Bibcode2006AstL...32..759G. 
  7. 7.0 7.1 7.2 7.3 Casagrande, L.; Schönrich, R.; Asplund, M.; Cassisi, S.; Ramírez, I.; Meléndez, J.; Bensby, T.; Feltzing, S. (June 2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s): Improved astrophysical parameters for the Geneva-Copenhagen Survey". Astronomy & Astrophysics 530: A138. doi:10.1051/0004-6361/201016276. ISSN 0004-6361. Bibcode2011A&A...530A.138C. 
  8. 8.0 8.1 8.2 8.3 Schofield, Mathew; Chaplin, William J.; Huber, Daniel; Campante, Tiago L.; Davies, Guy R.; Miglio, Andrea; Ball, Warrick H.; Appourchaux, Thierry et al. (2019-03-01). "The Asteroseismic Target List for Solar-like Oscillators Observed in 2 minute Cadence with the Transiting Exoplanet Survey Satellite" (in en). The Astrophysical Journal Supplement Series 241 (1): 12. doi:10.3847/1538-4365/ab04f5. ISSN 0067-0049. Bibcode2019ApJS..241...12S. 
  9. "gam Ind". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=gam+Ind. 
  10. "The Colour of Stars". Australia Telescope, Outreach and Education. Commonwealth Scientific and Industrial Research Organisation. December 21, 2004. http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html. Retrieved 2012-01-16.