HD 2454

HD 2454
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pisces
Right ascension 00h 28m 20.042s[1]
Declination +10° 11′ 23.30″[1]
Apparent magnitude (V) 6.04[2]
Characteristics
Spectral type F5 V Sr[3]
B−V color index 0.447 ± 0.005[4]
Astrometry
Radial velocity (Rv)−9.9±0.2[5] km/s
Proper motion (μ) RA: +42.022 mas/yr[1]
Dec.: −180.181 mas/yr[1]
Parallax (π)26.2526 ± 0.057 mas[1]
Distance124.2 ± 0.3 ly
(38.09 ± 0.08 pc)
Absolute magnitude (MV)3.24±0.03[2]
Details
Mass1.23[6] M☉
Radius1.6±0.1[7] R☉
Luminosity4.59[4] L☉
Surface gravity (log g)0.14±4.22[6] cgs
Temperature6,508±221[6] K
Metallicity [Fe/H]−0.32[2] dex
Rotation3 days[8]
Age1.865[6] Myr
Other designations
88 G. Piscium[9], BD+09°47, FK5 2028, HD 2454, HIP 2235, HR 107, SAO 109224[10]
Database references
SIMBADdata

HD 2454 is a probable binary star system in the zodiac constellation of Pisces. With an apparent visual magnitude of 6.04,[2] it is near the lower limit of visibility to the naked eye under good seeing conditions. An annual parallax shift of 26.3 mas as measured from Earth's orbit provides a distance estimate of 124 light years. It has a relatively high proper motion, traversing the celestial sphere at a rate of 0.208 arcseconds per year,[11] and is moving closer to the Sun with a heliocentric radial velocity of −10 km/s.[5]

The visible component of this system is an F-type main-sequence star with a stellar classification of F5 V Sr,[3] showing an abnormally strong line of singly-ionized strontium (Sr II) at a wavelength of 4077 Å.[12] It has an estimated 1.23[6] times the mass of the Sun and 1.6[7] times the Sun's radius. The star is about 1.9[6] billion years old with a rotation period of around three days.[8] It is radiating 4.6[4] times the Sun's luminosity from its photosphere at an effective temperature of around 6,508 K.[6]

HD 2454 was the first star to be identified as a Barium dwarf, by Tomkin et al. (1989),[13] and is the brightest such object.[2] It displays a mild overabundance of the element barium, which is hypothesized to have been accreted when an unresolved white dwarf companion was passing through the asymptotic giant branch (RGB) stage.[13]

The visible component displays significant overabundances of three s-process peak elements that are generated during the RGB phase, as well as a mild overabundance of carbon.[14] In contrast, it shows severe depletion of lithium and beryllium, as well as a notable underabundance of boron. The surface abundances of these lighter elements may have been altered during the mass transfer process, having been previously consumed in the core region of the companion.[15]

  1. ^ a b c d Cite error: The named reference GaiaEDR3 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Gray2011 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 c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference deBruijne2012 was invoked but never defined (see the help page).
  6. ^ a b c d e f g Cite error: The named reference David2015 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Allen2006 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Baliunas1996 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Gould1879 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference Lepine2005 was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference gray2009 was invoked but never defined (see the help page).
  13. ^ a b Cite error: The named reference Tomkin1989 was invoked but never defined (see the help page).
  14. ^ Cite error: The named reference Roederer2012 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference Boesgaar2005 was invoked but never defined (see the help page).