In 1997, astronomers were surprised to discover that Earth actually has another “moon,” formerly unknown because of the way it moves in the galaxy.

Dubbed Cruithne, this “moon” (which is actually an asteroid orbiting the Sun) circles around the Earth quite differently from the familiar orb we see every night. Instead of traveling in a tight circle around the Earth, Cruithne actually follows what scientists call a “horseshoe” orbit, where the celestial body creates multiple, smaller rings that are connected and eventually compose a large circle. Essentially, it looks like a doodle.

Cruithne’s path is massive. As it swings away from the Earth, Cruithne actually comes close to Venus and Mars only to travel back near Earth again. And though it orbits the Sun once a year, it takes Cruithne about 800 years to travel all of the rings that compose its massive orbit.

Unlike the Moon, we don’t really know much about Cruithne except that it’s pretty tiny, only five kilometers across. We also know that it’s gravity is so weak that you could easily send yourself into space. Other than that, our other moon remains quite a mystery.

Considering we only discovered this moon and the idea of horseshoe orbits less than 20 years ago, researchers hope studying the new moon will reveal new information that will help us understand our galaxy more. And who knows, maybe even discover more moons.

(h/t The Conversation)

Update: We’ve added the quotation marks around the word “moon” since Cruithne orbits the Sun, not Earth and is not technically a moon. Updated throughout.