Astronomers have recently validated the existence of a new “quasi-moon” that travels alongside Earth. This small asteroid, designated 2025 PN7, is on a synchronized orbit with our planet as it journeys around the Sun. Discovered in August 2025 by the Pan-STARRS observatory in Hawaii, the asteroid measures approximately 20 meters in diameter and is believed to have been accompanying Earth for roughly 60 years.
A quasi-moon, also referred to as a quasi-satellite, differs from a true moon. Unlike our natural satellite, which is gravitationally bound to Earth and orbits it directly, a quasi-moon revolves around the Sun, paralleling Earth”s own path. The trajectory of 2025 PN7 allows it to remain in close proximity to our planet for extended durations, creating the visual effect that it is orbiting Earth. Observers on Earth perceive its motion as a looping figure-eight or horseshoe pattern, a phenomenon resulting from the interplay of gravitational forces from both Earth and the Sun.
This new quasi-moon”s orbit closely matches that of Earth, completing its solar revolution in about one year. At times, it may drift slightly ahead of Earth, while at other moments, it falls behind, maintaining a delicate gravitational equilibrium. Unlike mini-moons, which may orbit Earth temporarily for months or years before departing, quasi-moons like 2025 PN7 can remain in this stable configuration for centuries.
While scientists have previously identified other short-term companions, including Kamo”oalewa (2016 HO3) and 2023 FW13, 2025 PN7 is notable for its stability and longevity. Astronomers stress that it poses no risk to Earth, remaining millions of kilometers away from both our atmosphere and the orbit of the Moon.
The study of quasi-moons offers valuable insights into orbital resonance, which refers to the gravitational interactions that allow these asteroids to maintain their synchronized motion with Earth. Their relative closeness also makes them intriguing targets for future space exploration, as they might provide important information about the early Solar System”s history. Though our true Moon remains the only natural satellite of Earth, discoveries like 2025 PN7 serve as a reminder of the dynamic nature of the space surrounding our planet and the occasional alignment of other cosmic bodies with Earth”s movement.
