Asteroid researchers from Universidad Complutense de Madrid Ciudad Universitaria have discovered a small asteroid that is going into orbit around the Earth starting in September, 2024.
It has been dubbed a “mini-moon” in the media, but it is not really a moon and will only be in orbit for a couple months. (To qualify as a moon, it would have to complete at least one full Earth orbit and this object will only loop around our planet in a horseshoe-like path before sliding off into space.)
Just 32 feet across, the rock is officially titled 2024 PT5 in NASA’s Small-Body database. It is too small and too distant to be viewed without a high-powered professional telescope. At its closest, it will be five times the distance of the moon from Earth.
In their paper published in the journal Research Notes of the AAS, Carlos de la Fuente Marcos and Raúl de la Fuente Marcos describe how the Earth tends to capture asteroids on a regular basis and outline their calculations showing the path of 2024 PT5 as it comes close to Earth.
Prior research has shown that many asteroids fall into partial or full elliptical paths around the Earth before eventually being flung away. Back in 2006, for example, a small asteroid circled the Earth for approximately a year—and another one did so for several years before leaving in 2020.
In this new effort, the researchers were looking at a small asteroid that was discovered last month as part of the Asteroid Terrestrial-Impact Last Alert System. Prior research had shown that the asteroid was not on a collision course with Earth, and the researchers suspected it might instead become bound by the planet's gravity for a while.
By noting its current size, speed and path, the pair were able to calculate its path over the next few months. They found that it was going to come close enough to the Earth to become bound by its gravity, if only for a couple of months.
