Quasi-satellite
A quasi-satellite is an asteroid that orbits the Sun in step with a planet, appearing to loop around the planet.
A quasi-satellite is an object that orbits the Sun with almost exactly the same period as a planet, but on a slightly different, more eccentric path. Seen from the planet, it seems to trace a loop around it once a year, as if it were a moon, even though it is not gravitationally bound.
Earth has several known quasi-satellites. The best studied is 469219 Kamoʻoalewa, discovered in 2016 by the Pan-STARRS survey in Hawaii. Its name comes from a Hawaiian chant and refers to an oscillating fragment. It is the target of China's Tianwen-2 sample-return mission.
Quasi-satellite arrangements last only decades to centuries before the object drifts away. Because Kamoʻoalewa's spectrum resembles weathered lunar rock, some researchers suggest that quasi-satellites could include fragments of the Moon thrown off by impacts, which then settled into Earth-like orbits around the Sun.
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