Earth has a new buddy. NASA astronomers have detected an asteroid that is constantly circling the Earth as part of its orbit around the sun. This “quasi-satellite,” known as 2016 HO3, has been with us for nearly a century — and will probably stay with us for centuries to come.

The video below, from NASA’s Center for Near-Earth Object Studies, shows 2016 HO3’s very odd trajectory: Like many objects in the solar system, 2016 HO3 orbits the sun. But almost a century ago, it wandered close enough to us that it’s now constantly getting tugged by Earth’s gravity, forcing it to make loops around our planet. READ MORE