Minimoon
A minimoon is a small asteroid temporarily captured into orbit around Earth for a few months or years.
A minimoon is a small asteroid that becomes temporarily captured by Earth's gravity and follows a looping path around our planet before escaping back into orbit around the Sun. These objects are typically only a few metres across.
Only a handful have been observed. 2006 RH120, about 2 to 3 metres across, orbited Earth for about a year from 2006 to 2007. 2020 CD3, found in February 2020, was another, and in 2024 the asteroid 2024 PT5 was temporarily bound to Earth for about two months, from late September to late November, though it did not complete a full orbit.
Models suggest that at any time there may be at least one minimoon of a metre or so around Earth. They would make convenient targets for future spacecraft, because they come so close. Some may be fragments of the Moon: 2024 PT5's spectrum appears similar to lunar rock.
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