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Mini-moons, also known as temporary moons or secondary satellites, are small objects that are temporarily captured by Earth's gravity and begin to orbit around our planet.
These mini-moons are usually asteroids or comet fragments that are trapped in an elliptical orbit around the Earth.
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Unlike our Moon, which is much larger and has a stable orbit, mini-moons have more unstable orbits and their stay in our system may be temporary, as they may eventually escape Earth's gravity or collide with Earth.
The detection and study of mini-moons is a constantly evolving field of research, and so far only a few mini-moons have been discovered around the Earth.
One of the best-known mini-moons is 2006 RH120, also known as "Rama", which was temporarily captured by Earth's gravity in 2006 before escaping back into space.
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Another famous mini-moon is 2020 CD3, which was discovered in 2020 and also had a brief sojourn in our orbit before continuing on its cosmic path.