An asteroid heading towards Earth is predicted to have a unique fate: instead of crashing through our planet’s atmosphere, it is expected to become trapped in orbit, turning into a mini-moon. However, this will be a brief visit, as it is likely to remain within Earth’s gravitational pull for only two months.
The asteroid, designated 2024 PT5, was discovered on August 7 and is approximately 10 meters (33 feet) in diameter.
Two astronomers from the Complutense University of Madrid, Carlos de la Fuente Marcos and Raúl de la Fuente Marcos, have analyzed the orbit of the object and determined that it will be captured in Earth’s orbit for a short period between September 29 and November 25. Afterward, it will return to orbiting the Sun and continue its journey through the Solar System.
In other words, for a total of 56.6 days, Earth will temporarily have two moons (or, more accurately, one proper Moon and one mini-moon).
The study notes that 2024 PT5 is “unlikely to be artificial,” meaning it is probably not just a piece of space debris, which can often be mistaken for mini-moons. The researchers suggest it may be an Arjuna asteroid, a near-Earth object with an orbit similar to Earth’s. These asteroids are named after an ancient prince from the Kuru Kingdom in present-day India, who is a central figure in the Hindu epic Mahābhārata.
Unfortunately, you probably won’t be able to catch a glimpse of the mini-moon while it’s in Earth’s orbit. According to the NASA JPL Small-Body Database, 2024 PT5 has an absolute magnitude of 27.6, making it too dim to be seen through most amateur telescopes.
So-called mini-moons have visited Earth before. In 1981, asteroid 2022 NX1 became a short-lived mini-moon. It quickly left Earth’s orbit, only to return as a mini-moon in 2022. It’s expected to return again in 2051.
2024 PT5 is also predicted to make multiple mini-moon appearances. The asteroid is expected to revisit Earth’s orbit in January 2025, before leaving again and returning in 2055.
The study is published in the journal *Research Notes of the American Astronomical Society*.
