Earth has a new companion in space – a small asteroid named 2025 PN7.
NASA confirmed this week that the object, discovered by the University of Hawaii’s Institute for Astronomy, is officially classified as a “quasi-moon.” This rare type of celestial object moves almost perfectly in sync with Earth. While it’s not a true moon, it follows a very similar orbit around the Sun, making it look like it’s shadowing our planet.
What Makes 2025 PN7 Special
Researchers estimate that 2025 PN7 is between 18 and 36 meters wide – about the height of a small office building. While that’s tiny by space standards, it’s large enough to join Earth’s extended neighborhood.
Unlike the real Moon, which is gravitationally bound to Earth, this asteroid isn’t held by our planet’s pull. Instead, it’s like a runner keeping pace on the same track – nearby, steady, but never actually connected.
A 60-Year Companion With a Temporary Stay
According to NASA’s Jet Propulsion Laboratory (JPL), 2025 PN7 has likely been accompanying Earth for roughly six decades. If its orbit stays stable, it will continue doing so until about 2083, before eventually drifting away into deep space.
When it’s closest, the asteroid comes within 4 million kilometers (about ten times farther than the Moon). At its farthest, it can be 17 million kilometers away. That ebb and flow happens due to the gravitational tug-of-war between the Sun and neighboring planets.
The Discovery: From a Faint Speck to a Confirmed Quasi-Moon
The University of Hawaii team spotted 2025 PN7 earlier this year using the Pan-STARRS telescope system during a regular sky survey. At first, it appeared as a faint dot moving slowly across the night sky. But after weeks of monitoring, the object was found to be following Earth’s exact pace around the Sun.
After confirming its unique motion, NASA’s Center for Near-Earth Object Studies (CNEOS) officially designated 2025 PN7 as a quasi-moon – one of only a handful ever discovered.
Only a Few Quasi-Moons Exist
Astronomers have confirmed just eight quasi-moons orbiting near Earth so far. Each one offers rare insight into how gravity shapes asteroid paths and how near-Earth objects behave over long periods.
Studying these companions helps refine orbital models, improve predictions for near-Earth asteroids, and reveal how Earth’s gravitational influence extends far beyond our atmosphere.
Why Quasi-Moons Matter for Future Exploration
For scientists, quasi-moons aren’t just fascinating oddities – they’re valuable tools. Because they’re close, stable, and relatively easy to reach, these objects could serve as testing sites for future robotic missions or practice runs for asteroid exploration.
Understanding how quasi-moons move also helps mission planners prepare for potential asteroid defense strategies and expand knowledge about the dynamic system surrounding our planet.
A Quiet Companion on Earth’s Endless Journey
Asteroid 2025 PN7 won’t ever replace our Moon or shine nearly as bright, but it’s still an incredible find.
It’s a silent traveller – orbiting with us, loop after loop – reminding us that even in the vastness of space, Earth rarely travels alone.
