Epsilon Canis Minoris

ε Canis Minoris
Location of ε Canis Minoris (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Canis Minor
Right ascension 07h 25m 38.89613s[1]
Declination +09° 16′ 33.9541″[1]
Apparent magnitude (V) +5.002[2]
Characteristics
Spectral type G6.5 IIb[3]
U−B color index +0.774[2]
B−V color index +1.004[2]
Astrometry
Radial velocity (Rv)−7.8±1.3[4] km/s
Proper motion (μ) RA: −3.338 ± 0.385[5] mas/yr
Dec.: −8.497 ± 0.310[5] mas/yr
Parallax (π)4.2624 ± 0.2288 mas[5]
Distance770 ± 40 ly
(230 ± 10 pc)
Absolute magnitude (MV)−2.62[6]
Details[7]
Mass4.63±0.17 M☉
Radius45.51±4.34 R☉
Luminosity1,086.5±197.8 L☉
Surface gravity (log g)1.81±0.06 cgs
Temperature4,916±70 K
Metallicity [Fe/H]−0.12±0.10 dex
Rotational velocity (v sin i)8[8] km/s
Age140±10 Myr
Other designations
ε CMi, 2 CMi, BD+09°1643, GC 9908, HD 58367, HIP 36041, HR 2828, SAO 115425[9]
Database references
SIMBADdata

Epsilon Canis Minoris (ε Canis Minoris) is a suspected binary star[10] system in the equatorial constellation of Canis Minor. It is a fifth magnitude star, which means it is bright enough to be faintly visible to the naked eye.[2] Based upon an annual parallax shift of just 3.13 mas as seen from Earth,[1] this star is located roughly 770 light years from the Sun, give or take a 40 light year margin of error.[5]

This is an evolved G-type bright giant star with a stellar classification of G6.5 IIb.[3] It is most likely (99% chance) on the horizontal branch,[7] and is a barium star that shows an abnormal overabundance of barium in its spectrum.[11] This s-process element may have been accreted from a now white dwarf companion during a previous stage of its evolution.[10] The bright giant component has an estimated 4.63 times the mass of the Sun and has expanded to 45.5 times the Sun's radius. The star is radiating 1,087 times the Sun's luminosity from its enlarged photosphere at an effective temperature of about 4,916 K.[7]

  1. ^ a b c Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Jennens1975 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference perkins1989 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  5. ^ a b c d 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. ^ Cite error: The named reference Takeda2008 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Reffert2015 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Bernacca1970 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ a b Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Williams1975 was invoked but never defined (see the help page).