tl;dr: Astronomers using ESO's VLT with the CRIRES+ instrument have detected what may be the first exomoon—a Jupiter-mass object orbiting a brown dwarf (30+ Jupiter masses) that itself orbits the star CD-35 2722. The detection used the radial velocity method to spot wobbles in the brown dwarf, though the finding blurs conventional definitions since the "moon" is planet-sized and orbits a substellar object rather than a planet. Confirmation and detection of smaller exomoons will likely require ESO's upcoming Extremely Large Telescope.