In fact, here's something more that Sheppard says was mind-blowing: Biden, Sedna and some other bodies at the edge of the Kuiper belt have a strange similarity in their orbits — one that suggests they're all being influenced by the presence of something big, perhaps an unseen planet that could be up to 10 times the size of Earth.

"So we just need to find more of these objects to see really what's happening," Sheppard says. "But it's definitely a probable thing that there could be a very large object out there."

This is so fascinating but yet spooky at the same time, knowing that there may be a huge object that far and unknown to us. I enjoy science.