Overview
- The team published their results on Wednesday, July 22, 2026, reporting evidence from radial-velocity monitoring taken between October 2023 and February 2026 that a brown dwarf in CD-35 2722 shows a 170-day wobble consistent with an orbiting companion.
- The companion is huge by Solar System standards, with a minimum mass just under Jupiter and a host-to-satellite mass ratio of about 2.5 percent compared with the roughly 37-Jupiter-mass brown dwarf.
- Authors label the object an 'exosatellite' rather than a confirmed exomoon because there is no agreed definition of exomoons and because the companion orbits a brown dwarf rather than a planet.
- The detection used Doppler radial-velocity data from the VLT's CRIRES+ instrument and is, the team says, the first time this technique has produced evidence for a satellite around a brown dwarf; astrometry and direct imaging are needed to get the true mass and orbital inclination.
- Beyond classification, the system raises formation questions because the companion's size and eccentric orbit may favor direct collapse over moon-like core accretion, and researchers plan follow-up observations and to apply the method to other targets as ELT-era capabilities come online.