We still don’t know for sure if the mythical Planet 9 even exists, but if it does, researchers now believe the mystery planet might’ve been stolen from another star altogether.
Astronomers have never actually seen what they've taken to calling Planet 9, but researchers have inferred its existence from strange orbits of smaller bodies located in the Kuiper Belt beyond Neptune. Basically, they can’t see it, but they believe there’s something out there affecting the things around it. The prevailing theory is that Planet 9 (if it exists) probably formed around the same time as our solar system and is just too far out (way beyond Pluto) for us to see just yet.
But the latest theory is a bit more exciting. Space reports a new study by lead author Alexander Mustill, an astronomer at Lund University in Sweden, indicates the planet may have been “stolen” by our sun from another star approximately 4.5 billion years ago, when everything was a good bit closer together. They reached the conclusion by studying computer modeling data over how the planet may have come to exist within our solar system.
The team stresses there’s still a lot of work to be done to prove this theory true (not to mention the existence of Planet 9 in general), but it’s fascinating to think what secrets Planet 9 could hold. You know, if we ever manage to actually find it.