#Asteroid the size of a ferris wheel could be a chunk of the Moon: study

The saying “I love you to the moon and back” may be in the past if Earth’s only natural satellite is breaking apart.

Earth’s moon may have taken a hit in the past, as scientists have identified an asteroid that they believe to be a giant boulder of lunar origin soaring through our orbit.

The asteroid was first discovered in 2016 by astronomers using the Pan-STARRS telescope — an acronym for Panoramic Survey Telescope and Rapid Response System — in Hawaii, according to a new study published in the journal Communications Earth & Environment. What they saw was a space rock that measured between 150 and 190 feet across, or about the size of a Ferris wheel, which is actually a fairly small asteroid compared to some, reported CNN on Thursday.

The “quasi-satellite,” which refers to an asteroid that orbits the sun but stays close to Earth, is known to fly within a range of 9 million miles from our home planet. Researchers estimate that it arrived about 500 years ago.

At about 4 million times more faint than the dimmest observable star, the asteroid can be difficult to spot by some telescopes at certain times of the year. So it wasn’t until they had the Large Binocular Telescope on Arizona’s Mount Graham International Observatory turn its sights toward the asteroid that they began to understand its origins.

They found that the surface of the asteroid, called Kamo’oalewa after a traditional Hawaiian creation story, reflects light in a manner very similar to our moon, suggesting that the two objects share a mineral profile, which they also based on lunar samples taken from NASA’s Apollo missions.

“I looked through every near-Earth asteroid spectrum we had access to, and nothing matched,” Ben Sharkey, lead study author and doctoral student at the University of Arizona’s Lunar & Planetary Laboratory, said in a statement.

Sharkey’s team, under the supervision of adviser Vishnu Reddy, a University of Arizona associate professor of planetary sciences, exhausted all other possibilities for the rock’s progeny.

“We doubted ourselves to death,” said Reddy, who co-authored the study.

The recent reopening of the Mount Graham telescope gave researchers the opportunity for a closer look.

“This spring, we got much-needed follow-up observations and went, ‘Wow, it is real,’” Sharkey said. “It’s easier to explain with the moon than other ideas.”

Kamo’oalewa’s unique orbit also hints at its moon parent — with a slight tilt unlike any of the other asteroids known to circle Earth.

Renu Malhotra, another co-author and distinguished professor of planetary sciences, said it’s not the “garden-variety near-Earth asteroid,” which doesn’t get the quasi-satellite distinction unless something extraordinary put it there.