Astronomy:Iota2 Cygni

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Short description: A-type main sequence star in the constellation Cygnus


Iota2 Cygni
Observation data
Equinox J2000.0]] (ICRS)
Constellation Cygnus
Right ascension  19h 29m 42.36s[1]
Declination +51° 43′ 47.2″[1]
Apparent magnitude (V) 3.76[2]
Characteristics
Spectral type A5V[3]
B−V color index +0.148±0.001[2]
Astrometry
Radial velocity (Rv)−19.5±2.7[2] km/s
Proper motion (μ) RA: +20.59[1] mas/yr
Dec.: +128.33[1] mas/yr
Parallax (π)26.88 ± 0.11[1] mas
Distance121.3 ± 0.5 ly
(37.2 ± 0.2 pc)
Absolute magnitude (MV)+0.91[2]
Details
Mass1.80[4] M
Radius3.83+0.40
−0.36
[5] R
Luminosity34.5±0.5[5] L
Surface gravity (log g)3.91[4] cgs
Temperature8,216±279[4] K
Rotational velocity (v sin i)240[6] km/s
Age577[4] Myr
Other designations
ι2 Cyg, 10 Cygni, BD+51° 2605, GC 26947, HD 184006, HIP 95853, HR 7420, SAO 31702[7]
Database references
SIMBADdata

Iota2 Cygni, Latinized from ι2 Cygni and often simply called ι Cygni,[8] is a single[9] star in the constellation Cygnus. It is visible to the naked eye as a white-hued point of light with an apparent visual magnitude of 3.76.[2] Located around 121.3 light-years distant from the Sun based on parallax,[1] it is drifting closer with a radial velocity of −19.5 km/s and is expected to come to within 92 light-years in around 783,000 years.[2]

This it is an A-type main-sequence star with a stellar classification of A5V,[3] a star that is currently fusing its core hydrogen. It is around 577[4] million years old and is spinning rapidly with a projected rotational velocity of 240 km/s.[6] The star has 1.8[4] times the mass of the Sun and 3.8[5] times the Sun's radius. It is radiating 35[5] times the luminosity of the Sun from its photosphere at an effective temperature of 8,216 K.[4] Based on rapid changes in the strength of a singly-ionized calcium absorption line, the star is likely host to a circumstellar disk.[10]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (November 2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 Chesneau, O. et al. (2010). "Time, spatial, and spectral resolution of the Hα line-formation region of Deneb and Rigel with the VEGA/CHARA interferometer". Astronomy and Astrophysics 521: A5. doi:10.1051/0004-6361/201014509. Bibcode2010A&A...521A...5C. https://hal.archives-ouvertes.fr/hal-00501515. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal 804 (2): 146, doi:10.1088/0004-637X/804/2/146, Bibcode2015ApJ...804..146D. 
  5. 5.0 5.1 5.2 5.3 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  6. 6.0 6.1 Zorec, J.; Royer, F. (January 2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, Bibcode2012A&A...537A.120Z. 
  7. "iot02 Cyg". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=iot02+Cyg. 
  8. Kaler, Jim. "Kappa, Iota Cygni". STARS. http://stars.astro.illinois.edu/sow/kappacyg.html. 
  9. 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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E 
  10. Montgomery, Sharon L.; Welsh, Barry Y. (October 2012). "Detection of Variable Gaseous Absorption Features in the Debris Disks Around Young A-type Stars". Publications of the Astronomical Society of the Pacific 124 (920): 1042–1056. doi:10.1086/668293. Bibcode2012PASP..124.1042M.