Prepare for an out-of-this-world event! This autumn, Earth is set to gain a temporary companion – a tiny asteroid called 2024 PT5. This ‘mini-moon’ will grace our planet’s orbit for a period of two months, between September 29th and November 25th, before breaking free from Earth’s gravitational pull.
While it’s too small to be visible to the naked eye or even through binoculars or home telescopes, professional telescopes will be able to capture its journey across the cosmos. Dr. Jennifer Millard, host of the Awesome Astronomy podcast, explained to BBC’s Today programme, “Professional telescopes will be able to pick it up. So, you’ll be able to look out for lots of wonderful pictures online of this little dot moving past the stars at great speed.”
This cosmic visitor was discovered on August 7th by NASA’s Asteroid Terrestrial-Impact Last Alert System (ATLAS). 2024 PT5, measuring approximately 33 feet (10 meters) wide, hails from the Arjuna asteroid belt, a region of space rocks orbiting the sun near Earth. This isn’t the first time Earth has had a temporary mini-moon. In 1981 and again in 2022, another asteroid, 2022 NX 1, briefly became Earth’s companion. Scientists predict 2024 PT5 will make a return visit to Earth’s orbit in 2055.
The American Astronomical Society has predicted 2024 PT5 will enter Earth’s orbit on September 29th and exit on November 25th. “It’s not going to complete a full revolution of our planet, it’s just going to kind of have its orbit altered, just twisted slightly by our planet and then it’ll continue on its merry way,” Millard explained.
Studies indicate that if an asteroid travels at a slow speed of roughly 3,540 km/h, Earth’s gravitational pull can temporarily capture it. This is precisely what will happen to 2024 PT5. Dr. Millard emphasized, “This story highlights just how busy our solar system is and how much there is out there that we haven’t discovered because this asteroid was only discovered this year. There are tens of thousands, if not hundreds of thousands, of objects out there that we haven’t discovered and so I think this highlights the importance of us being able to continually monitor the night sky and find all of these objects.”
