HD 187123

HD 187123

HD 187123 has a planetary system with at least two planets in it. Artist's rendition of planets HD 187123 b and c.
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cygnus
Right ascension 19h 46m 58.1122s[1]
Declination +34° 25′ 10.281″[1]
Apparent magnitude (V) 7.83[2]
Characteristics
Spectral type G2V[3]
B−V color index 0.661±0.010[2]
Astrometry
Radial velocity (Rv)−16.91(12)[1] km/s
Proper motion (μ) RA: 142.591(15) mas/yr[1]
Dec.: −123.715(18) mas/yr[1]
Parallax (π)21.7166 ± 0.0157 mas[1]
Distance150.2 ± 0.1 ly
(46.05 ± 0.03 pc)
Absolute magnitude (MV)4.41[2]
Details
Mass1.06±0.02[4] M
Radius1.17±0.03[4] R
Luminosity1.44±0.02[4] L
Surface gravity (log g)4.32±0.03[4] cgs
Temperature5,853±53[4] K
Metallicity [Fe/H]0.121±0.030[5] dex
Rotational velocity (v sin i)2.15±0.50[5] km/s
Age5.6±1.3[4] Gyr
Other designations
BD+34°3708, HD 187123, HIP 97336, SAO 68845, LTT 15779[6]
Database references
SIMBADdata

HD 187123 is a single,[7] yellow-hued star with two exoplanetary companions in the northern constellation of Cygnus. It has an apparent visual magnitude of 7.83,[2] making it an 8th magnitude star that is too faint to be visible with the naked eye. However, it should be easy target with binoculars or small telescope. The system is located at a distance of 150 light years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −17 km/s.[1]

This is an ordinary G-type main-sequence star with a stellar classification of G2V.[3] The physical properties of this star are sufficiently similar to the Sun that it has been considered a solar analog, although the metallicity is higher.[8] It is estimated to be five or six billion years old and is spinning with a projected rotational velocity of 2 km/s.[5] The star has a similar mass to the Sun but is slightly larger with 117% of the Sun's radius. It is radiating 1.44 times the luminosity of the Sun from its photosphere at an effective temperature of 5,853 K.[4]

  1. ^ a b c d e f Cite error: The named reference Gaia DR3 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference Anderson_Francis_2012 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Gray_et_al_2001 was invoked but never defined (see the help page).
  4. ^ a b c d e f g Cite error: The named reference Bonfanti_et_al_2016 was invoked but never defined (see the help page).
  5. ^ a b c Cite error: The named reference Feng2015 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference Ginski_et_al_2012 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference Soubiran_Triaud_2004 was invoked but never defined (see the help page).