This ‘mini-moon’ is actually an asteroid — named ‘2024 PT5’ — which is about the size of a school bus. When it whizzed past Earth on Sunday (Sept 29), it would be temporarily pulled by our planet’s gravity. However, the Earth’s double delight of possessing two ‘Moons’ will be short-lived as the asteroid will revolve around the Earth only for 57 days.The asteroid will jettison the Earth’s gravity and disappear into deep space by late November.
The ‘2024 PT 5’ was discovered on August 7, 2024, by the Asteroid Terrestrial-impact Last Alert System (ATLAS), an automated system funded by the US space agency Nasa and run from Hawaii. The system is used to monitor near-Earth asteroids.
In a report published in Research Notes of the American Astronomical Society (RNAAS), astronomers say the orbital properties of 2024 PT5 resemble that of asteroids that come from the Arjuna asteroid belt, ‘a sparsely resonant population of small Near-Earth Objects (NEOs).’
Dr Anil Kumar, head of Isro’s Network for Space Objects Tracking and Analysis (NETRA), which is also keeping a close watch on the asteroid, has also confirmed that the ‘mini moon’ is part of the Arjuna Asteroid grouping. The grouping was named in honour of Arjuna, a central character in epic Mahabharata, who was known for his archery skills and bravery. Like the swift arrows of Arjuna, the name reflects both the asteroid’s swift movement through the solar system and its unpredictable nature.
The asteroid, measuring just 10 meters in diameter, is 350,000 times smaller than Earth’s regular Moon, which has a diameter of 3,476 km, making it too small to detect without specialised equipment.
Carlos de la Fuente Marcos and Raúl de la Fuente Marcos, two scientists who reported it, said, “NEOs that follow horseshoe paths, and approach our planet at close range and low relative velocity, may undergo mini-moon events in which their geocentric energy becomes negative for hours, days or months, but without completing one revolution around Earth”.
Marcos said this is not the first time mini Moons appear around the Earth. It happened in 1997, 2013 and 2018, a report said.
On Nov 25, asteroid ‘2024 PT5’ will part ways with the Earth and continue its solo trajectory in cosmos. It’s expected to pass by Earth again in 2055.