Earth has a new space companion — a small asteroid named 2025 PN7, recently confirmed by NASA. Though it’s not a real moon, it travels around the Sun in almost the same orbit as Earth, making it look like it’s following our planet through space.
This “quasi-moon”, first discovered by astronomers at the University of Hawaii, is estimated to be 18 to 36 metres wide — about the height of a small building. While tiny by space standards, its discovery is fascinating for scientists studying how asteroids move near Earth.
The asteroid 2025 PN7 is not directly orbiting Earth like our natural moon. Instead, it travels around the Sun on a path that nearly matches Earth’s. This unique movement makes it appear as if it’s staying close to us, even though it’s actually an independent traveler in space.
NASA scientists describe it as being like “a friendly runner keeping pace on the same track — close enough to notice but never touching.”
Researchers believe 2025 PN7 has been moving near Earth’s orbit for almost 60 years, and it may continue to do so until around 2083, before eventually drifting away into deep space.
At its closest point, the asteroid comes within about 4 million kilometres of Earth — nearly 10 times farther than our moon. At its farthest, it moves out to 17 million kilometres, depending on how the Sun’s and planets’ gravity affect its orbit.
This makes 2025 PN7 a safe visitor — it poses no danger to Earth, as it stays far outside our atmosphere and cannot collide with our planet.
Discovery of the Quasi-Moon
Astronomers at the University of Hawaii first noticed the object during a routine sky survey in 2025. It appeared as a small, faint dot slowly moving against the background of stars.
After weeks of observation and orbital analysis, NASA confirmed that the asteroid’s path was nearly identical to Earth’s, officially classifying it as a quasi-moon — a rare type of object that temporarily shares our planet’s orbit around the Sun.
What is a Quasi-Moon?
- It’s an asteroid that orbits the Sun, but its path is so similar to Earth’s that it appears to travel alongside our planet.
- Unlike our natural Moon, it doesn’t orbit Earth but shares Earth’s solar orbit, creating a temporary association.
These orbits are temporary. Eventually, gravitational forces from the Sun or other planets pull the asteroid away, ending its close companionship with Earth.
