This autumn, Earth is set to welcome a temporary celestial guest: a small asteroid that will become a ‘mini-moon’ or ‘second moon’ from September 29 to November 25. While this event has sparked excitement among stargazers and space enthusiasts, the asteroid will not be visible to the naked eye due to its small size and low brightness.
Known as asteroid 2024 PT5, this celestial body measures about 33 feet in diameter and hails from the Arjuna asteroid belt, which is home to rocks with orbits similar to that of Earth. It was first identified on August 7 by NASA’s Asteroid Terrestrial-Impact Last Alert System (ATLAS). Dr. Jennifer Millard, host of the Awesome Astronomy podcast, stated that only professional telescopes will be capable of capturing images of this mini-moon. “You’ll be able to find stunning pictures online of this tiny dot racing past the stars,” Millard shared in an interview with the BBC.
Although asteroid 2024 PT5 will be temporarily captured by Earth’s gravitational pull, it will not complete a full orbit around the planet. Dr. Millard explained, “Its trajectory will be slightly altered by our planet before it continues on its journey.” Some asteroids come alarmingly close to Earth, with some passing as near as 2.8 million miles (4.5 million km). Moving at a relatively slow speed of approximately 2,200 mph (3,540 km/h), 2024 PT5 will be briefly held by Earth’s gravity.
As 2024 PT5 prepares to become Earth’s mini-moon, it’s worth noting that other asteroids have made similar visits in the past. Many more may have gone unnoticed, while some, such as asteroid 2022 NX1, have returned for repeat appearances, becoming mini-moons in both 1981 and 2022. If you happen to miss this event, there’s no need to worry—2024 PT5 is expected to make another pass near Earth in 2055.
This intriguing occurrence highlights the vibrant activity within our solar system and the numerous undiscovered celestial objects that are still out there. Dr. Millard remarked, “This story illustrates just how busy our solar system is and how much remains to be explored. This asteroid was only detected earlier this year.”
As the mini-moon’s arrival approaches, both astronomers and enthusiasts are eager to experience this celestial phenomenon, even if it requires professional equipment to catch a glimpse of this fleeting visitor.
