Iota Chamaeleontis

Iota Chamaeleontis
Location of ι Chamaeleontis (circled)
Observation data
Epoch J2000      Equinox ICRS
Constellation Chamaeleon
Right ascension 09h 24m 09.224s
Declination –80° 47′ 12.758″
Apparent magnitude (V) 5.34
Characteristics
Spectral type F3/5 III/V
U−B color index +0.01
B−V color index +0.454±0.003
Astrometry
Radial velocity (Rv)−3.57±0.66 km/s
Proper motion (μ) RA: –138.717 mas/yr
Dec.: +134.880 mas/yr
Parallax (π)17.3133±0.0528 mas
Distance188.4 ± 0.6 ly
(57.8 ± 0.2 pc)
Absolute magnitude (MV)+1.52
Details
Mass1.88 M☉
Radius3.4 R☉
Luminosity19.1 L☉
Temperature6,514 K
Metallicity [Fe/H]−0.04 dex
Rotational velocity (v sin i)129.7 km/s
Age1.2±0.1 Gyr
Other designations
ι Cha, CD−80°329, FK5 2753, GC 13066, HD 82554, HIP 46107, HR 3795, SAO 258530
Database references
SIMBADdata

Iota Chamaeleontis is a single star in the southern circumpolar constellation of Chamaeleon. Its name is a Bayer designation that is Latinized from ι Chamaeleontis, and abbreviated Iota Cha or ι Cha. This star is visible to the naked eye as a dim, yellow-white hued point of light, having an apparent magnitude of about 5.3. Based upon parallax measurements, this star is 188.4 light-years (57.8 pc) away from the Sun, but it is drifting closer with a radial velocity of −4 km/s.

Spectra of this star taken in different years have been given types of F3IV/V and F5III, leading to a mean published type of F3/5 III/V, with the suspicion that the spectrum is variable. It is an F-type star, likely an evolving subgiant.

Iota Cha has 1.9 times the mass of the Sun with 3.4 times the Sun's radius. It is 1.2 billion years old with a high rate of spin, showing a projected rotational velocity of 130 km/s. This is giving it an oblate shape with an equatorial bulge some 9% larger than the polar radius. The star is radiating 19.1 times the Sun's luminosity from its photosphere at an effective temperature of 6,514 K. An infrared excess suggests a circumstellar disk of dust is orbiting at a distance of 8.3 AU from the star with a mean temperature of 200 K.

References

  1. 1 2 3 4 5 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.
  2. 1 2 3 4 5 6 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.
  3. ↑ Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0. Bibcode:1975mcts.book.....H.
  4. ↑ Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
  5. 1 2 3 Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  6. 1 2 Bochanski, John J.; et al. (April 2018). "Fundamental Properties of Co-moving Stars Observed by Gaia". The Astronomical Journal. 155 (4): 17. arXiv:1801.00537. Bibcode:2018AJ....155..149B. doi:10.3847/1538-3881/aaaebe. S2CID 119256051. 149.
  7. 1 2 3 4 5 Schofield, Mathew; et al. (2019), "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
  8. ↑ Nordström, B.; et al. (2004). "The Geneva-Copenhagen survey of the Solar neighbourhood. Ages, metallicities, and kinematic properties of ˜14 000 F and G dwarfs". Astronomy and Astrophysics. 418: 989–1019. arXiv:astro-ph/0405198. Bibcode:2004A&A...418..989N. doi:10.1051/0004-6361:20035959. S2CID 11027621.
  9. 1 2 Reiners, Ansgar (January 2006), "Rotation- and temperature-dependence of stellar latitudinal differential rotation", Astronomy and Astrophysics, 446 (1): 267–277, arXiv:astro-ph/0509399, Bibcode:2006A&A...446..267R, doi:10.1051/0004-6361:20053911, S2CID 8642707
  10. ↑ "iot Cha". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 25 January 2016.
  11. ↑ 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.
  12. ↑ Allen, J. S. "The Classification of Stellar Spectra". UCL Department of Physics and Astronomy: Astrophysics Group. Retrieved 1 January 2014.
  13. ↑ van Belle, Gerard T. (March 2012). "Interferometric observations of rapidly rotating stars". The Astronomy and Astrophysics Review. 20 (1): 51. arXiv:1204.2572. Bibcode:2012A&ARv..20...51V. doi:10.1007/s00159-012-0051-2. S2CID 119273474.
  14. ↑ Cotten, Tara H.; Song, Inseok (July 2016). "A Comprehensive Census of Nearby Infrared Excess Stars". The Astrophysical Journal Supplement Series. 225 (1): 24. arXiv:1606.01134. Bibcode:2016ApJS..225...15C. doi:10.3847/0067-0049/225/1/15. S2CID 118438871. 15.