Earth gains new tiny 'quasi-moon' 2025 PN7 and it may stay for the next 60 years

Meet 2025 PN7: Earth’s Newest Quasi-Moon May Stay for 60 Years (Representational Image: Canva)

On a still August night, astronomers were scanning the heavens. Their work uncovered an unexpected find close to home. A tiny space rock, known as 2025 PN7, probably orbited nearby for some six decades. The finding sheds light on rare quasi-moons and their mysterious behaviour.

What Is 2025 PN7 and How Was It Found?

2025 PN7 is a tiny asteroid classified as a quasi-moon. Unlike typical moons, it orbits the Sun while staying near Earth. It completes a full solar orbit every year, just like our planet. The object was first spotted by the Pan-STARRS observatory on Hawaii’s Haleakala volcano. Astronomers observed it on August 29, 2025.

Archival data revealed it has maintained an Earth-like orbit for years. Its small size and faint presence made detection very challenging. “It is small, faint and rarely visible,” said Carlos de la Fuente Marcos. He is a researcher at Complutense University of Madrid. The study was published on September 2 in the Research Notes of the American Astronomical Society. French amateur astronomer Adrien Coffinet initially reported the asteroid on August 30, 2025.

How Close Does 2025 PN7 Come to Earth?

At its nearest, 2025 PN7 comes 186,000 miles (299,337 kilometres) from Earth. Its average distance is about 238,855 miles (384,400 kilometres) which is similar to the Moon’s orbit. “It can only be detected when close to Earth,” de la Fuente Marcos said. The asteroid’s visibility windows are very rare and unpredictable. “It remained undetected for such a long time,” he added.

What Makes 2025 PN7 Special Among Quasi-Moons?

2025 PN7 is just 62 feet (19 metres) wide, requiring powerful telescopes for observation. De la Fuente Marcos described it as “the smallest and least stable quasi-satellite of Earth.” Unlike temporary mini-moons, which orbit briefly, quasi-moons remain near Earth much longer. For example, 2024 PT5 orbited Earth for only two months.

Another well-known quasi-moon is Kamo‘oalewa, thought to be an ancient lunar fragment. Researchers believe 2025 PN7 will stay in its current near-Earth orbit for the next 60 years. Afterwards, the Sun’s gravity will push it into a horseshoe orbit. Dr. Teddy Kareta, assistant professor at Villanova University, explained the object’s nature. “It is almost certainly a rocky, natural object,” he said.

Why Study Quasi-Moons Like 2025 PN7?

Quasi-moons are extremely rare and fascinating. The Planetary Society describes them as “a gravitational sleight of hand”. From Earth, they seem to orbit us but are mainly influenced by the Sun. Understanding these objects helps scientists learn about our cosmic neighbourhood.

De la Fuente Marcos suggests more quasi-moons may yet be discovered. “These satellites are full of surprises,” he said. The study’s insights could lead to improved asteroid tracking techniques. More significantly, they address fundamental questions about Earth's past and future activities in space.

The finding of 2025 PN7 proves that our solar system has numerous secrets. Scientists will keep following it up closely. Every new discovery makes us understand the hidden dynamics of space more.