HD 210056

HD 210056
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Octans
Right ascension 22h 11m 54.98416s[1]
Declination −76° 06′ 57.6788″[1]
Apparent magnitude (V) 6.13±0.01[2]
Characteristics
Spectral type K0 III[3]
U−B color index +0.82[4]
B−V color index +1.00[4]
Astrometry
Radial velocity (Rv)24±1[5] km/s
Proper motion (μ) RA: −59.351 mas/yr[1]
Dec.: −40.005 mas/yr[1]
Parallax (π)11.1656 ± 0.0205 mas
Distance292.1 ± 0.5 ly
(89.6 ± 0.2 pc)
Absolute magnitude (MV)+1.41[6]
Details[7]
Mass1.59±0.07 M☉
Radius7.72±0.13 R☉
Luminosity29.7±0.5 L☉
Surface gravity (log g)2.86±0.10 cgs
Temperature4,849±37 K
Metallicity [Fe/H]−0.08±0.03 dex
Rotational velocity (v sin i)<1.5[8] km/s
Age2.10±0.22[9] Gyr
Other designations
68 G. Octantis[10], CD−76°1120, CPD−76°1549, GC 31004, HD 210056, HIP 109584, HR 8432, SAO 258006[11]
Database references
SIMBADdata

HD 210056, also known as HR 8432, is a solitary orange hued star located in the southern circumpolar constellation Octans. Eggen (1993) listed it as a member of the old disk population.[12]

The object has an apparent magnitude of 6.13,[2] making it barely visible to the naked eye. Based on parallax measurements from the Gaia satellite, the object is estimated to be 292 light years distant.[1] It appears to be receding with a heliocentric radial velocity of 24 km/s.[5] At its current distance, HD 210056's brightness is diminished by 0.2 magnitudes due to interstellar dust. It has an absolute magnitude of +1.41.[13]

This is an evolved giant star with a stellar classification of K0 III. It has 1.59 times the mass of the Sun but has expanded to 7.72 times its girth.[7] It radiates 29.7 times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,849 K.[7] Based on asteroseismologic measurements, HD 210056 is estimated to be 2 billion years old.[9] The star has about 90% of the Sun's metallicity — what astronomers define a star's abundance of chemical elements heavier than helium.[7] It currently spins slowly with a projected rotational velocity lower than 1.5 km/s.[9]

  1. ^ a b c d Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b Cite error: The named reference Tycho2000 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Houk1975 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Johnson1966 was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ a b c d Cite error: The named reference Ottoni2022 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference DeMed2014 was invoked but never defined (see the help page).
  9. ^ a b c Cite error: The named reference Aguirre2020 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Gould1879 was invoked but never defined (see the help page).
  11. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  12. ^ Cite error: The named reference Eggen1993 was invoked but never defined (see the help page).
  13. ^ Cite error: The named reference Gontcharov2017 was invoked but never defined (see the help page).