Earth to get a new moon? Meet 2024 PT5, our temporary mini-moon for 53 days!

Earth is about to welcome a new mini-moon for a short period. Starting from September 29 until November 25, a small asteroid named 2024 PT5 will temporarily be captured by Earth's gravity, according to researchers Carlos de la Fuente Marcos and Raúl de la Fuente Marcos from Universidad Complutense de Madrid.

The asteroid, approximately 10 meters wide, was discovered through the Asteroid Terrestrial-Impact Last Alert System. Researchers found that its size, speed, and trajectory are suitable for it to be caught by Earth's gravitational field for 53 days. During this time, it will orbit Earth before resuming its path through the solar system.

"2024 PT5 will circle the Earth one time before it escapes back into space," the researchers stated in their paper. This event is known as a "temporarily captured flyby," where an asteroid enters Earth's gravity but does not make multiple orbits.


Similar occurrences have been observed in the past. For example, in 2006, an asteroid orbited Earth for nearly a year, and another did so for several years before leaving in 2020. These temporary captures occur frequently as Earth intermittently captures small asteroids from the Near-Earth Object (NEO) population.

Asteroids like 2024 PT5 follow paths known as "horseshoe orbiters" due to their shape around Earth and the Sun. These bodies often approach Earth at low speeds, allowing temporary capture. Most mini-moons, however, do not complete a full orbit around Earth before returning to their heliocentric paths.

The origins of the 2024 PT5 asteroid are also of interest. Researchers suggest it likely comes from the Arjuna asteroid group, which has an orbit around the Sun similar to Earth’s. This conclusion is based on the asteroid’s path closely matching other natural objects, dismissing the notion that it is space debris.