Overview
- The Science study reports a Saturn-mass (~0.22 Jupiter) free-floating planet located about 9,785 light-years (≈3,000 parsecs) away toward the Milky Way bulge.
- The microlensing event, designated KMT-2024-BLG-0792/OGLE-2024-BLG-0516, was detected on May 3, 2024 by KMTNet and OGLE and fortuitously observed by ESA’s Gaia at L2.
- Gaia recorded six passes over 16 hours, providing a timing offset that enabled a microlens parallax measurement and broke the mass–distance degeneracy.
- This is the first confirmed case securing both mass and distance for a free-floating planet, with the Saturn-like mass supporting an origin in a planetary system followed by ejection.
- Scientists say the method paves the way for population studies of rogue worlds, with NASA’s Nancy Grace Roman Space Telescope expected to boost detections in coming years.