HD 197027

HD 197027

HIP 102152
Credit: ESO/Digitized Sky Survey 2
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Capricornus
Right ascension 20h 41m 54.6336s[1]
Declination −27° 12′ 57.4154″[1]
Apparent magnitude (V) 9.15±0.02[2]
Characteristics
Spectral type G3 V[3]
U−B color index +0.30[4]
B−V color index +0.65[2]
Astrometry
Radial velocity (Rv)−43.9±0.3[5] km/s
Proper motion (μ) RA: +175.628[1] mas/yr
Dec.: −15.593[1] mas/yr
Parallax (π)12.7715 ± 0.0164 mas[1]
Distance255.4 ± 0.3 ly
(78.3 ± 0.1 pc)
Absolute magnitude (MV)4.74[6]
Details
Mass0.97[7] M☉
Radius1.08+0.07
−0.05[8] R☉
Luminosity1.19[6] L☉
Surface gravity (log g)4.40±0.02[9] cgs
Temperature5718±5[9] K
Metallicity [Fe/H]−0.020±0.005[9] dex
Rotational velocity (v sin i)1.78±0.12[9] km/s
Age6.92±0.69[9] Gyr
Other designations
CD−27°14976, CPD−27°7079, HD 197027, HIP 102152, SAO 189585[10]
Database references
SIMBADdata

HD 197027 (HIP 102152) is a star in the constellation Capricornus. It has an apparent magnitude of 9.15,[2] making it readily visible through a telescope but not to the naked eye. The object is located at a distance of 255 light years but is approaching the Solar System with a heliocentric radial velocity of −44 km/s.[5]

HD 197027 has a stellar classification of G3 V, indicating that it is an ordinary G-type main-sequence star like the Sun. It has only 97% the mass of the Sun[7] but 108% of its radius.[8] It shines at 119% the luminosity of the Sun[6] from its photosphere at an effective temperature of 5,718 K,[9] similar to the Sun's 5,778 K. HD 197027's metallicity – elements heavier than helium – is similar to the Sun.[9] At an older age of 6.92 billion years, it spins with a projected rotational velocity of about 2 km/s.[9]

Since its measured properties of this star are very similar to those of the Sun, it has been considered a candidate older solar twin.[11] The abundances of 21 elements overall are more similar to the Sun than any other known solar twin. [citation needed] Its Iron Abundance is -0.03 with an error value of 0.02 Fe/H. (The value comes from the Hipparcos Extended Catalog.)[12]

  1. ^ a b c d e Cite error: The named reference EDR3 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Tycho2000 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference Houk1982 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference Paunzen2022 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. ^ a b c Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference apj774 was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Stassun2019 was invoked but never defined (see the help page).
  9. ^ a b c d e f g h Cite error: The named reference dosSantos2016 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. ^ ESO, The life cycle of a Sun-like star (annotated), from European Southern Observatory, 28 August 2013
  12. ^ "HD 197027 Star Distance, Age, Colour and other Facts - Universe Guide". universeguide.com. 10 January 2024. Retrieved 2024-01-19.