Research reveals that 2025 PN7 is a newly identified quasi-satellite in a 1:1 mean-motion resonance with Earth, suggesting a complex asteroid relationship.
When the first asteroid in an Earth-like orbit, 1991 VG, was found in 1991 December by the Spacewatch Project, it was argued that it was a candidate interstellar space probe, but it is now thought to be natural. Over three decades later, the number of known asteroids in Earth-like orbits exceeds 100, forming the so-called Arjuna secondary asteroid belt, the closest to Earth. Out of the Arjunas and not counting those which can be temporarily captured as mini-moons of Earth, quasi-satellites are our closest companions. Here we show that 2025 PN 7 is a quasi-satellite, alongside known objects Cardea, Kamo‘oalewa, 277810, 2013 LX 28 , 2014 OL 339 , 2023 FW 13 . They are all engaged in a 1:1 mean-motion resonance with our planet, but they are not gravitationally bound to it.
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Marcos et al. (2025) studied this question.
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