(WWJ) A new discovery in a night sky: A "mini moon" orbiting the Earth.
Michael Narlock, head of astronomy at the Cranbrook Institute of Science in Bloomfield Hills, says the find was made earlier this month by researchers in Arizona.
"A moon is just about anything that orbits a larger body; a parent object," he explained, in an interview Wednesday with WWJ Newsradio 950's Dan Jenkins.
Narlock said this mini moon is, in fact, an asteroid. And although we didn't know about it until recently, scientists believe it has been in orbit around Earth for roughly three years.
"So, it will be with us for awhile," he said. "This is the second known asteroid that has been captured. The last one was back in 2006, and it stayed with us for a year and-a-half."
Narlock says the asteroid will eventually fall out of Earth's orbit, but that there are most likely countless others like it out there, just waiting to be found.
A spot of bad news: Amateur astronomers with telescopes at home will have a tough time finding the mini moon because of its size.
"It's not a very big object. It's, you know, less than 15 feet across," Narlock said. "So it's a very, very small chunk of rock, essentially, that's been snatched by Earth's gravity/"