HD 40409

HD 40409
Observation data
Epoch J2000      Equinox J2000
Constellation Dorado
Right ascension 05h 54m 06.05633s[1]
Declination −63° 05′ 23.1963″[1]
Apparent magnitude (V) 4.65[2]
Characteristics
Spectral type K2 III[3]
B−V color index 1.022±0.045[2]
Astrometry
Radial velocity (Rv)+25.1±0.8[2] km/s
Proper motion (μ) RA: +118.57[1] mas/yr
Dec.: +572.93[1] mas/yr
Parallax (π)36.9551 ± 0.2499 mas[1]
Distance88.3 ± 0.6 ly
(27.1 ± 0.2 pc)
Absolute magnitude (MV)2.56[2]
Details[4]
Mass1.12 M☉
Radius4.79 R☉
Luminosity11.2 L☉
Surface gravity (log g)3.27 cgs
Temperature4,858 K
Metallicity [Fe/H]+0.07 dex
Age7.91 Gyr
Other designations
CD−63°218, FK5 2452, GJ 9194, HD 40409, HIP 27890, HR 2102, SAO 249390[5]
Database references
SIMBADdata

HD 40409 is a suspected astrometric binary[6] star system in the southern constellation of Dorado. It is a faint system but visible to the naked eye with an apparent visual magnitude of 4.65.[2] Based upon an annual parallax shift of 36.96 mas,[1] it is located 88 light years away from the Sun. It is moving further away with a heliocentric radial velocity of +25 km/s.[2] The system has a relatively high proper motion, traversing the celestial sphere at the rate of 0.57 arcseconds per year along a position angle of 14.51°.[7]

Based on the stellar classification of K2 III assigned by Gray et al. (2006),[3] the visible component is a K-type giant star. In contrast, Keenan and McNeil (1989) gave it a somewhat less evolved classification of K2 III–IV.[8] It is about eight billion years old with 12% more mass than the Sun, and has expanded to 4.8 times the Sun's radius. The star is radiating 11 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,858 K.[4]

  1. ^ a b c d e f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Gray2006 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Wittenmyer2016 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Bakos2002 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference perkins1989 was invoked but never defined (see the help page).