HD 38529 (138 G. Orionis) is a binary star approximately 138 light-years away in the constellation of Orion.
HD 38529 A is a yellow subgiant star, which has also been classified as a main sequence dwarf of spectral type G4V.
Two substellar companions are known in orbit around this star, including one with a mass near the deuterium fusion limit that is often used as the dividing line between giant planets and brown dwarfs.
[11] Astrometric measurements from the Hipparcos satellite gave a best fit inclination of 160° and a true mass 37 times that of Jupiter, turning this planet into a brown dwarf.
[12] Further study of the system using Hubble Space Telescope astrometry revised the mass of HD 38529 c downwards to 17.7 Jupiter masses and suggested the presence of an additional planet, orbiting in the gap between HD 38529 b and c.[13] The possible third planet was refuted after additional radial velocity measurements were collected.