Overview
- Researchers led by Kevin Hoy reported in Nature on July 22 that high‑precision VLT/CRIRES+ radial‑velocity monitoring from October 2023 to February 2026 detected a clear 170‑day wobble in the brown dwarf CD‑35 2722 b.
- The inferred companion has a minimum mass about 90% that of Jupiter and orbits the ~30–37 Jupiter‑mass brown dwarf in a system roughly 71–73 light‑years away.
- The team calls the object an exosatellite because it orbits a brown dwarf that itself orbits a star, but the International Astronomical Union’s 2018 wording would classify a planet‑mass body around a brown dwarf as an exoplanet.
- Confirming the object’s true mass, orbit geometry and formation history will require follow‑up astrometry, higher‑resolution imaging with ELT‑class telescopes, or other methods to distinguish core accretion from direct collapse.
- If verified, the system will broaden the known architectures of planetary systems, force clearer taxonomy for moons and planets, and guide searches for similar massive satellites with upcoming instruments and surveys.