An asteroid first detected in 2025 has been orbiting Earth for at least 60 years, according to orbital calculations, with archival images confirming its presence since the 1960s. The object, designated 2025 PN7, is a quasi-satellite rather than a true moon, following a heliocentric path that temporarily aligns with Earth’s orbit.
The asteroid 2025 PN7 was first identified by the Pan-STARRS 1 telescope on 2 August 2025, but its orbital data revealed it had been shadowing Earth for decades. Researchers Carlos de la Fuente Marcos and Raúl de la Fuente Marcos, in a 2025 paper published in Research Notes of the AAS, calculated that the object entered its quasi-satellite state around the mid-1960s and will remain in this configuration for about six more decades. The paper, titled Meet Arjuna 2025 PN7, the Newest Quasi-satellite of Earth,
details the object’s orbital mechanics and historical tracking (Spacedaily).
An asteroid spent roughly 60 years quietly shadowing Earth's
Orbital analysis of 2025 PN7 shows it completes one revolution around the Sun every 366 days, slightly longer than Earth’s 365-day year. This 1:1 resonance creates the illusion of a satellite in Earth’s sky, though the asteroid never enters Earth’s gravitational sphere. The European Space Agency (ESA) estimates its size at 14–30 meters, with an absolute magnitude of 26.3 (Spacedaily). However, the sources do not specify ESA’s role in this estimation, and the exact size remains unverified by the provided material.
The first evidence of 2025 PN7 came from a 2018 Dark Energy Camera image, which captured the asteroid as a faint dot amid stars. However, without a known orbit, the object went unnoticed until 2025. Astronomers used precovery techniques—re-examining archival data with updated orbital models—to trace its path backward. The JPL database now includes 36 observations, with the earliest dating to 11 December 2013 and the latest from 6 August 2026 (Spacedaily). The de la Fuente Marcos paper noted that the asteroid’s orbital model suggests it has been in a quasi-satellite state for 128 years, with its current trajectory expected to last until 2085 (Spacedaily).
Dinosaur-killing asteroid also created a dust cloud that insulated
Precovery is a critical tool in asteroid detection, allowing researchers to identify objects long after their initial discovery. For 2025 PN7, this method confirmed its presence in 2013 and earlier. The asteroid’s orbital calculations rest on 27 observations spanning 4,279 days, nearly 12 years, as of the 2025 study. This span is possible because astronomy has a word for finding an object before its discovery: precovery. Once enough recent observations reveal an orbit, software can calculate where the object should appear in older exposures. Researchers can then return to the archive and inspect a very small patch of an old image rather than searching the whole sky again (Source 1).
The asteroid’s orbital parameters are defined by JPL’s August 2026 data: an orbital period of about 366 days, a semimajor axis of 1.001 astronomical units, and an inclination just under two degrees. Its path is slightly more elongated than Earth’s, with an eccentricity of about 0.108. From a Sun-centered view, Earth and the asteroid follow separate orbits. In a frame that rotates with Earth, however, 2025 PN7 appears to loop in a pattern that mimics a satellite (Source 1).
Asteroid Facts
Quasi-satellites like 2025 PN7 occupy a unique orbital niche. While they share Earth’s solar orbit, they never approach close enough to be captured by the planet’s gravity. Instead, their elliptical paths create a looping appearance when viewed from Earth. This dynamic is temporary, as gravitational interactions with other celestial bodies will eventually disrupt the resonance (Spacedaily). Comparisons to other quasi-satellites, such as Kamo’oalewa, highlight the rarity of such objects. Kamo’oalewa has a longer residency in a quasi-satellite state, but 2025 PN7’s shorter duration underscores the transient nature of these orbits (Spacedaily).
NASA’s Center for Near Earth Object Studies (CNEOS) classifies 2025 PN7 as a near-Earth Apollo asteroid but not a potentially hazardous one. The asteroid’s small mass and distance from Earth mean it does not require monitoring for impact risks (science.nasa.gov). The sources note that the total mass of all asteroids in the solar system is less than that of Earth’s Moon, with most asteroids located in the main belt between Mars and Jupiter. Over 150 asteroids are known to have small companion moons, and binary or triple asteroid systems also exist (Source 3).
The case of 2025 PN7 illustrates how archival data and modern computational models can uncover hidden celestial patterns. As astronomers refine orbital predictions, the likelihood of discovering more quasi-satellites increases. However, the object’s benign trajectory reinforces the current consensus that Earth faces no immediate risk from such bodies (Spacedaily). The asteroid’s discovery also raises questions about how many similar objects remain undetected. With improved surveys and data-sharing, future missions may identify more quasi-satellites, expanding our understanding of solar system dynamics. For now, 2025 PN7 serves as a reminder of the intricate, ever-changing dance of celestial bodies in our cosmic neighborhood.
