Earth's Constant Companion Asteroid As Big as a Ferris Wheel Could Be A Fragment of the Moon, Study Suggests

New study claims that the mysterious asteroid that has been Earth's constant companion could be a fragment from the Moon. This asteroid, which measures about 190ft or is as big as a Ferris wheel, was discovered five years ago using the Pan-STARRS 1 asteroid survey telescope on Haleakala, Hawaii.

Dubbed as Kamo'oalewa, with the provisional designation of 2016 HO3, scientists know little about it, but the analysis showed that it is made from the material as the lunar rocks brought by Apollo missions of NASA.

According to Daily Mail, a team of experts led by the University of Arizona said that the origins of the asteroid remain a mystery, but it may have been debris from an impact event or gravitational breakup of a larger body during a closer encounter with Earth.

190ft Near-Earth Asteroid That Has Been Its Constant Companion Could Be A Fragment of the Moon, Study Suggests

(Photo : Wikimedia Commons)
Asteroid 2016 HO3 has an orbit around the sun that keeps it as a constant companion of Earth. Credit: NASA/JPL-Caltech

Quasi-Satellite Kamo'oalewa May Be a Fragment of the Moon

In the study, titled "Lunar-Like Silicate Material Forms the Earth Quasi-Satellite (469219) 2016 HO3 Kamoʻoalewa" published in Communications Earth & Environment, researchers described the clues that might explain the asteroid's origins.

One of these clues is its unusual orbit similar to Earth but slightly tilted, an atypical characteristic of any near-Earth asteroid. Study co-author Renu Malhorta, a professor in planetary sciences at the University of Arizona, said that it is unlikely that a garden-variety near-Earth asteroid would spontaneously move into a quasi-satellite orbit and that it will not remain in that orbit for long.

New Scientist reported that lead researchers Benjamin Sharkey and Vishnu Reddy at the University of Arizona used the university's Large Binocular Telescope and the Lowell Discovery Telescope to examine the spectrum of light bouncing off from the asteroid.

They found that it was unexpectedly red and discovered that Kamo'oalewa's spectrum did not match to other asteroids after comparing it to almost 2,000 spectra of other near-Earth asteroids. The only close match they found was with the lunar rocks that were brought back by Apollo missions, which hints that it may have been thrown from the lunar surface due to a strong impact.

Researchers said that finding its origins is like a missing piece of the puzzle. More so, determining how long it has been traveling with Earth is an even challenging question. They believe that the only way to do that would be to get a sample from the asteroid as what the Chinese space agency's ZhengHe mission plans to do in 2022.

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Earth's Constant Companion

NASA's Jet Propulsion Laboratory (JPL) predicts that asteroid 2016 HO3 will remain a companion to Earth for centuries to come. The asteroid orbits the Earth as the planet orbits the Sun. But unlike Moon, the asteroid is too distant to be considered a true satellite of Earth. Hence it is called a quasi-satellite.

Paul Chodas, manager of NASA's Center for Near-Earth Object (NEO) Studies at JPL, said that the asteroid is more locked to Earth than other quasi-satellites that have departed Earth's vicinities in the past years. It led them to conclude that it has been almost a century since it circles the Earth and is likely to continue on this path for centuries to come.