Earth will get a second moon for about two months this year, when a small asteroid begins orbiting our planet. The asteroid was discovered in August and is expected to become a mini-moon, orbiting Earth in a horseshoe shape from September 29 to November 25.
Researchers with the Asteroid Terrestrial-impact Last Alert System, a NASA-funded asteroid monitoring system, spotted the asteroid using an instrument in Sutherland, South Africa, and named it 2024 PT5.
Scientists from the Complutense University of Madrid tracked the asteroid’s orbit for 21 days and determined its future trajectory. 2024 PT5 comes from the Arjuna asteroid belt, which orbits the sun, according to their study published in Research Notes of the AAs.
But Earth’s gravitational pull will pull 2024 PT5 towards it, and just like our Moon, it will orbit our planet – but only for 56.6 days.
Other non-Earth objects (or NEOs) have already entered Earth’s orbit, but some do not complete a full revolution around Earth. Some, however, do and become mini-moons.
An asteroid called 2020 CD3 remained bound to Earth for several years before leaving the planet’s orbit in 2020, and another called 2022 NX1 became a mini-moon of Earth in 1981 and 2022 and will return again in 2051.
2024 PT5, larger than some other mini-moons, will also return to Earth’s orbit in 2055.
Earth’s gravity will pull it into its orbit, and the asteroid will have negative geocentric energy, meaning it will not be able to escape Earth’s gravitational pull. It will orbit Earth in a horseshoe shape before returning to heliocentric energy, meaning it will orbit the Sun again, like other planets and near-Earth objects in our galaxy.
Even after leaving orbit, it will remain near Earth for a few months, making its closest approach on January 9, 2025. Shortly thereafter, it will leave Earth’s vicinity until its trajectory brings it back into our orbit in about 30 years.
The study’s lead author, Carlos de la Fuente Marcos, told Space.com that the mini-moon will be too small to see with amateur telescopes or binoculars, but professional astronomers with more powerful tools will be able to spot it.
CBS News has reached out to Marcos for additional information and is awaiting a response.
