Earth will have a temporary 'mini moon' for two months

WASHINGTON : Earth’s moon will soon have some company — a “mini moon.” The mini moon, in fact a small asteroid, is about the size of a school bus, at 33 feet (10 meters) across. When it whizzes by Earth on Sunday, it will be temporarily trapped by our planet’s gravity and orbit the globe — but only for about two months.

The space rock — 2024 PT5 — was first spotted in August by astronomers at Complutense University of Madrid using a powerful telescope located in Sutherland, South Africa.

Short-lived mini moons are likely more common than we realize, says astronomer Richard Binzel of Massachusetts Institute of Technology. The last known one was detected in 2020.

This happens with some frequency, but we rarely actually observe them because they are incredibly small and extremely difficult to detect,” he said. “Only just recently have we developed a survey capability that detects them with any regularity.” Carlos de la Fuente Marcos and Raúl de la Fuente Marcos made the discovery, which was published in an American Astronomical Society.

This one won’t be visible to the naked eye or through amateur telescopes, but “can be observed with relatively large, research-grade telescopes,” Carlos de la Fuente Marcos said in an email.

Binzel, who was not involved in the research, said it’s not clear whether the space rock originated as an asteroid or as “a chunk of the moon that got blasted out.”.
Once freed from its gravitational lock with the larger body, the mini moon will orbit Earth nearly 57 days but not fully. On Nov. 25, it will break away from Earth and continue on its lonely way through the cosmos. It is expected to pass again in 2055.