Earth's moon isn't alone out there.
It turns out that a second large rocky body is orbiting our world, and has been for about a hundred years now.
The object, called asteroid 2016 HO3, was first spotted by NASA this April and follows Earth in a long, wobbly orbit around the Sun, drifting ahead of and behind our planet.
Here's what else we know about it so far:
Skye Gould/Tech Insider