Rho Gruis

Rho Gruis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Grus
Right ascension 22h 43m 29.97654s[1]
Declination −41° 24′ 51.6467″[1]
Apparent magnitude (V) 4.847[2]
Characteristics
Evolutionary stage horizontal branch[2]
Spectral type K0 III[3]
U−B color index +0.807[4]
B−V color index +1.026[4]
Astrometry
Radial velocity (Rv)30.89±0.15[5] km/s
Proper motion (μ) RA: +10.11[1] mas/yr
Dec.: −93.79[1] mas/yr
Parallax (π)14.16 ± 0.19 mas[1]
Distance230 ± 3 ly
(70.6 ± 0.9 pc)
Absolute magnitude (MV)0.685[2]
Details
Mass1.91[2] M☉
Radius12.15+0.19
−0.65[5] R☉
Luminosity66.9±1.3[5] L☉
Surface gravity (log g)2.62[2] cgs
Temperature4736.67+131.83
−36.67[5] K
Metallicity [Fe/H]−0.20[2] dex
Other designations
ρ Gru, CD−42° 16049, FK5 3818, HD 215104, HIP 112203, HR 8644, SAO 231265[6]
Database references
SIMBADdata

Rho Gruis, a Latinization of ρ Gruis, is a solitary[7] star in the southern constellation of Grus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.85.[2] Based upon an annual parallax shift of 14.16 mas as seen from the Earth,[1] the system is located about 230 light years from the Sun. It is drifting further away with a radial velocity of 31 km/s.[5]

This object is an evolved K-type giant star with a stellar classification of K0 III.[3] It has exhausted the supply of hydrogen at its core, causing it to cool and expand. At present it has 12[5] times the radius of the Sun. With 1.9 times the mass of the Sun[2] it is a red clump star,[2] which indicates it is on the horizontal branch generating energy through helium fusion at its core. It is radiating 67[5] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,737 K.[5]

Rho Gruis has two visual companions: a magnitude 14.0 star at an angular separation of 19.3″ along a position angle (PA) of 302°, as of 2011, and a magnitude 10.28 star with a separation of 114.20″ and a PA of 336°, as of 1999.[8]

  1. ^ a b c d e f Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d e f g h i Cite error: The named reference Liu2007 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Houk1978 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Cousins1983 was invoked but never defined (see the help page).
  5. ^ a b c d e f g h Cite error: The named reference GaiaDR2 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 Eggleton2008 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).