"After analyzing its trajectory, scientists concluded that the object maintains a 1:1 resonance with the Earth. In other words, it orbits the sun at the same time as our planet. From a distant perspective, this synchronicity makes it look as if the Earth is accompanied by a tiny asteroid-as if it had an additional moon. Unlike the moon, quasi-lunar moons are not gravitationally bound to the Earth. They are ephemeral companions, in cosmological terms, following their own path around the sun. Only at certain times do they come close enough to appear bound."
"In the case of 2025 PN7, its minimum distance is 299,000 kilometers, while at its farthest point it can reach 17 million km. For comparison, the moon remains at an average distance of 384,000 km from Earth. According to the article published in Research Notes of the AAS, the asteroid has been in a quasi-satellite phase since 1965, and is expected to remain so for 128 years. Some researchers estimate that 2025 PN7 will finally move away in 2083."
"So far, seven bodies have been confirmed that appear to accompany the planet in its orbit. Astronomers believe that more may be discovered in the future. Earth is a natural reservoir of quasi-lunars because the Earth's orbit is similar to that of certain nearby objects that inhabit the so-called Arjuna group of asteroids, a population that has only recently begun to be studied in greater detail. The Arjuna group does not form a ring like the asteroid belt between Mars and Jupiter, but comprises a legion of near-Earth rocks that orbit the sun on a similar path as our planet. Occasionally, some of these asteroids coincide with our trajectory and, depending on their orbital dynamics, are classified as quasi-lunar or mini moons."
Asteroid 2025 PN7, an Apollo-type near-Earth object detected by Pan-STARRS 1, has been confirmed as Earth's seventh quasi-lunar moon. The object maintains a 1:1 resonance with Earth, orbiting the sun in sync with the planet and appearing to accompany Earth from a distance. Quasi-lunar moons are not gravitationally bound and only sometimes approach closely enough to seem bound; 2025 PN7 ranges from about 299,000 km to 17 million km from Earth, compared with the Moon's average 384,000 km. The asteroid entered a quasi-satellite phase in 1965 and is expected to remain so for roughly 128 years, possibly departing around 2083. These temporary companions arise because Arjuna-group asteroids share orbital paths similar to Earth's and can become transient quasi-satellites or mini-moons.
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