Astronomy:Eta Canis Minoris

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Short description: Binary star system in the constellation Canis Minor
η Canis Minoris
Canis Minor constellation map.svg
Red circle.svg
Location of η Canis Minoris (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Canis Minor
Right ascension  07h 28m 02.07527s[1]
Declination +06° 56′ 31.0897″[1]
Apparent magnitude (V) 5.25[2] + 11.1[3]
Characteristics
Spectral type F0 III[3]
U−B color index +0.17[2]
B−V color index +0.22[2]
Astrometry
Radial velocity (Rv)+17.2[4] km/s
Proper motion (μ) RA: −2.955 ± 0.231[5] mas/yr
Dec.: −43.624 ± 0.197[5] mas/yr
Parallax (π)10.2691 ± 0.1452[5] mas
Distance318 ± 4 ly
(97 ± 1 pc)
Absolute magnitude (MV)0.1[6]
Details
η CMi A
Mass2.16[4] M
Luminosity57.5[4] L
Surface gravity (log g)3.66[7] cgs
Temperature7,505±66[4] K
Rotational velocity (v sin i)54[8] km/s
Age818[7] Myr
Other designations
η CMi, 5 CMi, BD+07°1729, GC 9970, HD 58923, HIP 36265, HR 2851, SAO 115477, ADS 6101, CCDM 07280+0657[9]
Database references
SIMBADdata

Eta Canis Minoris (η CMi, η Canis Minoris) is a binary star[3] system in the equatorial constellation of Canis Minor. It is approximately 318 light-years from Earth.

The primary component, η Canis Minoris A, is a yellow-white F-type giant with an apparent magnitude of +5.24. Its companion, η Canis Minoris B, is an eleventh-magnitude star located 4 arcseconds from the primary, though is actually around 440 astronomical unit|AU from the main star and takes around 5,000 years to orbit it.[10]

References

  1. 1.0 1.1 van Leeuwen, F. (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 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode1966CoLPL...4...99J. 
  3. 3.0 3.1 3.2 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. 
  4. 4.0 4.1 4.2 4.3 Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 23, doi:10.1088/0004-6256/150/3/88, 88, Bibcode2015AJ....150...88L. 
  5. 5.0 5.1 5.2 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. Jaschek, C.; Gomez, A. E. (1998), "The absolute magnitude of the early type MK standards from HIPPARCOS parallaxes", Astronomy and Astrophysics 330 (619–625): 619, Bibcode1998A&A...330..619J. 
  7. 7.0 7.1 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. 
  8. Royer, F. et al. (October 2002), "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i", Astronomy and Astrophysics 393: 897–911, doi:10.1051/0004-6361:20020943, Bibcode2002A&A...393..897R. 
  9. "eta CMi". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=eta+CMi. 
  10. Kaler, Jim, "Eta and Delta-1 CMi", Stars (University of Illinois), http://stars.astro.illinois.edu/sow/etacmi.html, retrieved 2017-09-01.