A near-Earth asteroid orbiting our planet is actually a piece of the moon, a new study has found. The asteroid is named Kamo'oalewa (a Hawaiian term that means "the oscillating fragment"), reported Live Science. The celestial object is a Ferris-wheel-size rock chunk that orbits within 14.4 million kilometres of Earth every April, the outlet further said. The asteroid was first discovered in 2016 and categorised as a quasi-satellite, a type of object that co-orbit with our planet. Their orbits are tied to Earth's and they never get away from the planet.
The study detailing Kamo'oalewa's categorisation as a lunar object has been published in the journal Nature.
The October 23 study describes a feasible way that an ancient asteroid impact could have shunted the space rock onto its current trajectory and suggests there could be more moon chunks floating around the solar system.
The researchers said in the study that the similarity of the object's reflectance spectrum to lunar silicates and its Earth-like orbit both suggest that it originated from the lunar surface.
Speaking about the discovery, Renu Malhotra, a planetary scientist at the University of Arizona, said in a statement: "We are now establishing that the moon is a more likely source of Kamo'oalewa."
The research began due to the unusual properties observed by scientists in Kamo'oalewa. They found that the light emitted and absorbed by the asteroid indicated that it was likely made of moon rock.
"We looked at Kamo'oalewa's spectrum only because it was in an unusual orbit. If it had been a typical near-Earth asteroid, no one would have thought to find its spectrum and we wouldn't have known Kamo'oalewa could be a lunar fragment," said Ms Malhotra said.
The team that carried out the research said these findings could give them a better understanding of hazardous near-Earth asteroids.
They will now try to figure out the conditions that could have pushed the rock into its orbit and to find out exactly when the impact took place.
