Gamma Indi

Gamma Indi
Observation data
Epoch J2000      Equinox J2000
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 mas/yr[2]
Dec.: +39.036 mas/yr[2]
Parallax (π)15.1909±0.0250 mas[2]
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. ^ a b 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. XHIP record for this object at VizieR.
  2. ^ a b c d e f g Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. 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. arXiv:1506.04568. Bibcode:2015A&A...580A..23P. doi:10.1051/0004-6361/201526413. ISSN 0004-6361.
  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. arXiv:1510.05666. Bibcode:2016AJ....151...59C. doi:10.3847/0004-6256/151/3/59.
  5. ^ a b Malaroda, S. (August 1975). "Study of the F-type 1 MK spectral types". 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". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. ISSN 1562-6873.
  7. ^ a b c d 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. arXiv:1103.4651. Bibcode:2011A&A...530A.138C. doi:10.1051/0004-6361/201016276. ISSN 0004-6361.
  8. ^ a b c d Schofield, Mathew; Chaplin, William J.; Huber, Daniel; Campante, Tiago L.; Davies, Guy R.; Miglio, Andrea; Ball, Warrick H.; Appourchaux, Thierry; Basu, Sarbani; Bedding, Timothy R.; Christensen-Dalsgaard, Jørgen; Creevey, Orlagh; García, Rafael A.; Handberg, Rasmus; Kawaler, Steven D. (2019-03-01). "The Asteroseismic Target List for Solar-like Oscillators Observed in 2 minute Cadence with the Transiting Exoplanet Survey Satellite". The Astrophysical Journal Supplement Series. 241 (1): 12. arXiv:1901.10148. Bibcode:2019ApJS..241...12S. doi:10.3847/1538-4365/ab04f5. ISSN 0067-0049.
  9. ^ "gam Ind". SIMBAD. Centre de données astronomiques de Strasbourg.
  10. ^ "The Colour of Stars". Australia Telescope, Outreach and Education. Commonwealth Scientific and Industrial Research Organisation. December 21, 2004. Archived from the original on 2013-12-03. Retrieved 2012-01-16.