When will Earth get its next mini-moon? A 1981 and 2022 visitor returns in...

Earth will soon lose its mini-moon that will fly away into space after completing its trip to our planet. Asteroid 2024 PT5 was captured by our planet's gravitational pull on September 29 and it will now zoom away on Nov 25. It originated in the Arjuna asteroid belt and was discovered on August 7 by the Asteroid Terrestrial-Impact Last Alert System (ATLAS). Space rocks that live in this region have orbits similar to Earth’s, which is about 93 million miles from the sun.

So, when will Earth get its next mini-moon? The next such cosmic wonder is nearly 27 years away. 

The asteroid was spotted travelling towards Earth by Carlos and Raúl de la Fuente Marcos, researchers at Spain’s Universidad Complutense de Madrid. They revealed the finding in a paper published in Research Notes of the AAS. 

Besides talking about the asteroid that would become Earth's mini-moon, the scientists also talked about previous occurrences. Our planet has had such moons in the past as well and one of them was the 2022 NX1. 

It was the first such recorded event, which happened in 1981. Asteroid 2022 NX1 was captured by Earth's gravity temporarily and soon flew away. It then returned in 2022 and again spent a short time acting like our planet's mini-moon. Both times, it did not complete a full revolution of Earth.

Now the same asteroid will return in 2051 and once again will be caught by the gravitational pull and orbit Earth. However, it is not known for how long it will stay and whether or not it will complete an orbit. 

Also Read: Earth has had two moons in the past. One of the mini-moons has visited twice and will return in 27 years

However, since astronomers are constantly keeping an eye on asteroids and monitoring incoming space rocks that might be a threat to us, there are chances that another such asteroid will be discovered in the interim. 

Other mini-moons

Asteroids regularly fly by Earth and sometimes the planet's gravity pulls them in. It is an extremely rare event.

Besides asteroids 2022 NX1 and 2024 PT, there have been a few other mini-moons as well. 

The authors state in their study that in 1992, asteroid 1991 VG was captured for a short time in the month of February. Another time this happened was in 2006, but this one was an even special one since it stayed with Earth for a full year. Asteroid 2006 RH120 was gravitationally bound to Earth till July 2007 after getting caught in July 2006. 

Then there was  2020 CD3 that remained in orbit for years and escaped early in May 2020.