HD 121056

HD 121056
Observation data
Epoch J2000      Equinox J2000
Constellation Centaurus
Right ascension 13h 53m 52.06131s[1]
Declination −35° 18′ 51.6918″[1]
Apparent magnitude (V) 6.17[2]
Characteristics
Evolutionary stage giant star
Spectral type K0 III[3]
B−V color index 1.01[4]
Astrometry
Radial velocity (Rv)5.60±0.13[1] km/s
Proper motion (μ) RA: −295.304±0.040 mas/yr[1]
Dec.: −68.458±0.058 mas/yr[1]
Parallax (π)15.6261 ± 0.0418 mas[1]
Distance208.7 ± 0.6 ly
(64.0 ± 0.2 pc)
Absolute magnitude (MV)+2.08[5]
Details
Mass1.60±0.18[6] M☉
Radius5.72[7] R☉
Luminosity15.8[7] L☉
Surface gravity (log g)3.261±0.105[2] cgs
Temperature4,867±49[2] K
Metallicity[Mg/H] 0.286±0.05 dex[2]
Metallicity [Fe/H]0.020±0.031[2] dex
Rotational velocity (v sin i)2.38±0.51[2] km/s
Age5.46[7] Gyr
Other designations
CD−34 9223, Gaia DR2 6169943210465504384, GJ 532.1, HD 121056, HIP 67851, HR 5224, TYC 7287-1874-1, 2MASS J13535209-3518517[8]
Database references
SIMBADdata

HD 121056, or HIP 67851, is an aging giant star with a pair of orbiting exoplanets located in the southern constellation of Centaurus. This star is dimly visible to the naked eye with an apparent visual magnitude of 6.17.[2] It is located at a distance of 209 light years from the Sun, based on parallax measurements, and is drifting further away with a radial velocity of 5.6 km/s.[1]

The spectrum of HD 121056 presents as an evolved K-type giant star with a stellar classification of K0 III.[9] It is presently ascending the red-giant branch, having exhausted the supply of hydrogen at its core.[4] The star is about 5.5[7] billion years old and is spinning with a projected rotational velocity of 2.4 km/s. HD 121056’s concentration of heavy elements is similar to the Sun, with a metallicity Fe/H index of 0.020±0.031, although the star is enriched in lighter rock-forming elements like magnesium and aluminum.[2] It has 1.6[6] times the mass of the Sun and has expanded to 5.72 times the Sun's radius.[7] The star is radiating 15.8[7] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,867 K.[2]

  1. ^ a b c d e f Cite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
  2. ^ a b c d e f g h i Cite error: The named reference Hojjatpanah2019 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference houk1999 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Jones2014 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference xhip was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Sousa_et_al_2018 was invoked but never defined (see the help page).
  7. ^ a b c d e f Cite error: The named reference soto2021 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Wittenmyer2014 was invoked but never defined (see the help page).