Astronomy:Mu2 Cancri

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Short description: Star in the constellation Cancer


Mu2 Cancri
Observation data
Equinox J2000.0]] (ICRS)
Constellation Cancer
Right ascension  08h 07m 45.85581s[1]
Declination +21° 34′ 54.5325″[1]
Apparent magnitude (V) +5.30[2]
Characteristics
Evolutionary stage Subgiant[3]
Spectral type G2 IV[4]
U−B color index +0.21[2]
B−V color index +0.63[2]
Astrometry
Radial velocity (Rv)−36.0±0.1[5] km/s
Proper motion (μ) RA: +23.610[1] mas/yr
Dec.: −68.122[1] mas/yr
Parallax (π)42.3605 ± 0.1251[1] mas
Distance77.0 ± 0.2 ly
(23.61 ± 0.07 pc)
Absolute magnitude (MV)+3.46[6]
Details
Mass1.192+0.017
−0.016
[7] M
Radius1.82[8] R
Luminosity3.782±0.015[1] L
Surface gravity (log g)3.97±0.02[7] cgs
Temperature5,809±59[7] K
Metallicity [Fe/H]0.11[7] dex
Rotational velocity (v sin i)3.7±0.3[6] km/s
Age5.64+0.35
−0.14
[7] Gyr
Other designations
μ Cnc, 10 Cancri, BD+22°1862, FK5 2630, HD 67228, HIP 39780, HR 3176, SAO 79959[9]
Database references
SIMBADdata

Mu2 Cancri is a solitary,[10] yellow-hued star in the zodiac constellation of Cancer. It is visible to the naked eye with an apparent visual magnitude of +5.30.[2] Based upon an annual parallax shift of 42.36 mas as seen from Earth,[1] this star is located 77 light-years from the Sun. It is drifting closer with a radial velocity of −36 km/s[5] and will make its closest approach in about 611,100 years when it passes at a distance of 16.8 light-years (5.2 parsecs).[11]

At the estimated age of 5.6 billion years,[7] Mu2 Cancri is an evolving G-type subgiant star[3] with a stellar classification of G2 IV.[4] It has 1.2[7] times the mass of the Sun and 1.8[8] times the Sun's radius. Mu2 Cancri has relatively high metallicity—what astronomers term the abundance of elements other than hydrogen and helium—having a 29% higher abundance compared to the Sun.[7] It is radiating 3.78[1] times the Sun's luminosity at an effective temperature of 5,809 K.[7] The star is spinning at a leisurely projected rotational velocity of 3.7 km/s.[6]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 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.
  2. 2.0 2.1 2.2 2.3 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 Abt, Helmut A. (May 2019), "The Evolutionary Status of GK Subgiants", The Astronomical Journal 157 (5): 5, doi:10.3847/1538-3881/ab11c6, 177, Bibcode2019AJ....157..177A. 
  4. 4.0 4.1 Gray, R. O. et al. (July 2006), "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 parsecs: The Northern Sample I", The Astronomical Journal 132 (1): 161–170, doi:10.1086/504637, Bibcode2006AJ....132..161G. 
  5. 5.0 5.1 de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: 14, doi:10.1051/0004-6361/201219219, A61, Bibcode2012A&A...546A..61D. 
  6. 6.0 6.1 6.2 Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics 542: A116, doi:10.1051/0004-6361/201118724, Bibcode2012A&A...542A.116A. 
  7. 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 Ramírez, I. et al. (February 2013), "Oxygen abundances in nearby FGK stars and the galactic chemical evolution of the local disk and halo", The Astrophysical Journal 764 (1): 78, doi:10.1088/0004-637X/764/1/78, Bibcode2013ApJ...764...78R. 
  8. 8.0 8.1 Takeda, Genya et al. (February 2007), "Structure and Evolution of Nearby Stars with Planets. II. Physical Properties of ~1000 Cool Stars from the SPOCS Catalog", The Astrophysical Journal Supplement Series 168 (2): 297–318, doi:10.1086/509763, Bibcode2007ApJS..168..297T. 
  9. "mu.02 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=mu.02+Cnc. 
  10. 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. 
  11. Bailer-Jones, C.A.L. et al. (2018), "New stellar encounters discovered in the second Gaia data release", Astronomy & Astrophysics 616: A37, doi:10.1051/0004-6361/201833456, Bibcode2018A&A...616A..37B.