NASA Confirms Earth Has Had ‘Mini’ Moon for a Century and Will for Centuries More

The “Man in the Moon” just got a new sibling.

Well, it’s not a new sibling. It’s actually been around for nearly a century, but researchers only last week confirmed that a small asteroid is in constant orbit with Earth and will remain so for years to come.

The “new” asteroid, called 2016 HO3, circles around Earth in a “stable” pattern. Researchers say it’s too distant from Earth to be considered a true satellite object, but it is the best example to date of a “near-Earth companion, or ‘quasi-satellite,'” NASA’s Jet Propulsion Laboratory wrote on its blog.

From Paul Chodas, manager of NASA’s Center for Near-Earth Object (NEO) Studies at the Jet Propulsion Laboratory in Pasadena, California:

“Since 2016 HO3 loops around our planet, but never ventures very far away as we both go around the sun, we refer to it as a quasi-satellite of Earth. One other asteroid – 2003 YN107 – followed a similar orbital pattern for a while over 10 years ago, but it has since departed our vicinity. This new asteroid is much more locked onto us. Our calculations indicate 2016 HO3 has been a stable quasi-satellite of Earth for almost a century, and it will continue to follow this pattern as Earth’s companion for centuries to come.”

JPL notes the ‘mini moon’ has a tilted orbit, causing it to “bob” up and down as it passes through Earth’s orbital plane. Also, 2016 HO3 spends half of its time closer to the sun than Earth and the other half of the year it is farther away.

“In effect, this small asteroid is caught in a game of leap frog with Earth that will last for hundreds of years,” JPL wrote on its blog.

Watch the video demonstration below to learn more about 2016 HO3’s slow dance with Earth.