Earth is getting ready to welcome a mini-moon into its orbit by the end of the month — but it’s for a limited time only, scientists say.
The space rock, an asteroid by the name of 2024 PT5, will show up to do a partial orbit around Earth between Sept. 29 and Nov. 25, before slipping back into space.
The phenomenon is dubbed a “mini-moon” by astronomers, and this particular piece of space material was discovered by NASA in early August. It hails from the Arjuna asteroid belt and was first detected by the NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS).
Unlike our own shining moon, this asteroid is tiny and will not be visible to us on Earth as researchers say it measures just 10 metres in length, or approximately the length of a school bus. Even with a strong telescope, it will be hard to see.
“The object is too small and dim for typical amateur telescopes and binoculars,” Carlos de la Fuente Marcos, one of the authors of the journal entry describing the asteroid, told Space.com.
“However, the object is well within the brightness range of typical telescopes used by professional astronomers.”
Speaking to ABC News, astrophysics professor Adam Frank from the University of Rochester explained the so-called mini-moon phenomenon:
“What we’re having here is an asteroid, which is basically a flying mountain in space that usually orbits close to the Earth, or orbits in the same distance from the Sun as the Earth, and it’s getting captured by the Earth’s gravity. And they’ll be part of the Earth Moon system,” he said. “It’ll orbit the Earth for maybe about two months, and then they’ll get flung back out. So we get a little, teeny, tiny, little moon for about two months.”
And while a piece of space rock orbiting so close to Earth can sound a bit unnerving, scientists say there’s no danger and 2024 PT5 is not on a collision course with our planet.
The last known mini-moon to orbit Earth was in 2022 when asteroid 2022 NX1 became a mini-moon for a few months. Before that, astronomers in 2020 identified a space rock called 2020 CD3, which orbited Earth for more than a year.
It’s expected that 2024 PT5 will return to orbit the Earth again in 2055.