Rubin Observatory expected to find more of Earth's mini-moons

Modeling by Grigori Fedorets of the University of Helsinki suggests the largest mini-moon around Earth is typically only about 75 cm across, with 3-meter asteroids captured every 10 to 20 years. The Vera C. Rubin Observatory's LSST survey should catch a mini-moon roughly every two years, and an ANTARES-based filter could raise that to two or three per year, opening the door to low-cost sample-return missions.

• Largest mini-moon around Earth is typically about 75 cm across
• A 3-meter asteroid is captured every 10 to 20 years
• LSST should find one mini-moon every 2 years, ANTARES 2–3 per year
• Only two mini-moons confirmed so far: 2006 RH120 and 2020 CD3