This year, Earth will briefly have a second moon when a small asteroid begins orbiting the planet. The asteroid, named 2024 PT5, was discovered in August and will act as a mini-moon from September 29 to November 25, revolving around Earth in a horseshoe-shaped orbit.
Spotted by NASA’s Asteroid Terrestrial-impact Last Alert System (ATLAS) in South Africa, the asteroid is from the Arjuna asteroid belt. Scientists from the Universidad Complutense de Madrid have tracked its path, determining that Earth’s gravitational pull will capture it for nearly two months before it returns to orbiting the sun.
This isn’t the first mini-moon Earth has captured; similar objects have orbited Earth temporarily in the past. 2024 PT5, larger than previous mini-moons, will return to Earth’s orbit in 2055. However, it will remain too small to be seen with amateur equipment.