HD 192310 (also known as 5 G. Capricorni or Gliese 785) is astar in the southernconstellation ofCapricornus. It is located in thesolar neighborhood at a distance of 28.7light-years (8.8parsecs), and is within the range of luminosity needed to be viewed from the Earth with the unaided eye. (According to theBortle scale, it can be viewed from dark suburban skies.) HD 192310 is suspected of being avariable star, but this is unconfirmed.
Thespace velocity components of this star are (U, V, W) =(–69, –13, –14) km/s. It is following an orbit through theMilky Way galaxy that has anorbital eccentricity of 0.18 at a mean galactocentric distance of 8.1 kpc.[11] The star will achieveperihelion in around 82,200 years when it comes within 20.18 ly (6.188 pc) of the Sun.[12]
The system has aNeptune-mass planet "b", discovered in 2010.[13] A second planet "c" was found in this system in 2011 by the HARPS GTO program, along with the now-doubtfulHD 85512 b and the planets of82 G. Eridani. The uncertainty in the mass of the second planet was much higher than for the first because of the lack of coverage around the full orbit. Both planets may be similar in composition to Neptune. They are orbiting along the inner and outer edges of thehabitable zone for this star.[8][14]
A study in 2023 updated the parameters of these two planets, and identified a number of additionalradial velocity signals. While most of these signals were attributed to stellar activity, one was considered a planet candidate. If real, this third planet would be asuper-Earth orbiting closer to the star than the two known planets.[15]: 31 However, another 2023 study did not find this candidate signal and also attributed it to stellar activity.[16]: 10
^abcJohnson, H. L.; et al. (1966). "UBVRIJKL photometry of the bright stars".Communications of the Lunar and Planetary Laboratory.4 (99): 99.Bibcode:1966CoLPL...4...99J.
^Samus, N. N.; Durlevich, O. V.; et al. (2009), "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)",VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S,1: B/gcvs,Bibcode:2009yCat....102025S
