Mu2 Gruis

For other stars with this Bayer designation, see μ Gruis.
Mu2 Gruis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Grus
Right ascension 22h 16m 26.54790s[1]
Declination −41° 37′ 37.8266″[1]
Apparent magnitude (V) 5.10[2]
Characteristics
Spectral type G8 III[3]
B−V color index +0.92[2]
Astrometry
Radial velocity (Rv)+12.50[4] km/s
Proper motion (μ) RA: −14.788[1] mas/yr
Dec.: −15.530[1] mas/yr
Parallax (π)13.1578 ± 0.1559 mas[1]
Distance248 ± 3 ly
(76.0 ± 0.9 pc)
Absolute magnitude (MV)+0.56[5]
Details
Radius9.97+0.32
−0.20[1] R☉
Luminosity56.37±0.78[1] L☉
Temperature5009+52
−79[1] K
Other designations
μ2 Gru, CD−42° 15846, HD 211202, HIP 109973, HR 8488, SAO 231063[6]
Database references
SIMBADdata

Mu2 Gruis, Latinized from μ2 Gruis, is a yellow-hued star or star system in the southern constellation of Grus. It is a suspected astrometric binary, showing a variation in proper motion due to gravitational acceleration.[7] Mu2 Gruis is visible to the naked eye with an apparent visual magnitude of 5.10.[2] The distance to this system, as determined using an annual parallax shift of 13.2 mas as seen from the Earth,[1] is around 248 light years. It is drifting further away with a heliocentric radial velocity of +12.5 km/s.[4]

The primary component is an evolved giant star with a stellar classification of G8 III.[3] It is a periodic variable star, showing a change in brightness with an amplitude of 0.004 magnitude at the rate of 7.50983 times per day.[8] With the supply of hydrogen at its core exhausted, the star has cooled and expanded until now it has 10 times the radius of the Sun. It is radiating 56[1] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 5,009 K.[1]

  1. ^ a b c d e f g h i j k Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c Cite error: The named reference Johnson1966 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 Gontcharov2006 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Anderson2012 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 Makarov2005 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference koen2002 was invoked but never defined (see the help page).