10/27/2025
🌍 A tiny companion has been quietly shadowing Earth, masquerading as our “second moon” for decades—only now have scientists caught it in the act.
Astronomers have confirmed the existence of 2025 PN7, a newly classified “quasi-moon”—a small asteroid that’s been following Earth in a synchronized orbit around the Sun. Unlike our true Moon, quasi-moons aren’t permanently bound to our planet, but share a cosmic waltz that makes them appear to circle us.
Discovered on July 30, 2025 by the Pan-STARRS1 telescope at Haleakalā Observatory in Hawaii, 2025 PN7 measures just 19 meters (62 feet) across—smaller than the meteor that exploded over Chelyabinsk in 2013. The asteroid is incredibly faint, with a magnitude of 26, and was missed for so long thanks to its dimness and “unfavorable” viewing angles.
What makes 2025 PN7 remarkable is both its stability and transience: orbital calculations show it’s been locked in this quasi-satellite configuration for the past 60–70 years and is expected to remain close for another six decades before drifting away. This makes it the smallest and least stable quasi-satellite currently known, offering scientists a rare glimpse into the dynamics of Earth’s celestial neighborhood.
This find hints at more such secret companions—future surveys, like those from the Vera C. Rubin Observatory, could unearth many more. Each new quasi-moon deepens our understanding of the solar system’s choreography and may unveil clues about planetary formation and near-Earth objects.
📄 RESEARCH PAPER
📌 Carlos de la Fuente Marcos et al, “Quasi-satellite 2025 PN7: the smallest and the least stable known quasi-satellite of Earth”, Research Notes of the American Astronomical Society (2025)