For a brief, but exciting, time last year, Earth had two moons. A small asteroid lingered close to our planet in its orbit around the Sun, temporarily caught by Earth’s gravity to become a far away mini-moon. A closer look at the space rock reveals a rather familiar origin: Earth’s mini-moon might actually be a broken-off piece of our regular Moon.

2024 PT5 is the second near-Earth asteroid scientists suspect was ejected from the moon's surface, the first being 469219 Kamo'oalewa, which a different team of scientists have traced to an old impact crater on the far side of the moon.

The asteroid is about 33 feet (10 meters) across and poses no danger to Earth. It joins another known lunar asteroid discovered in 2016 known as 469219 Kamo’oalewa. Scientists hope that as telescopes become more powerful, we will be able to detect more bits of the Moon that have been blasted free in ancient impacts.