The astronomer whose work helped kick Pluto out of the pantheon of planets says he has good reason to believe there's an undiscovered planet bigger than Earth lurking in the distant reaches of our solar system. That's quite a claim, because Mike Brown of Caltech is no stranger to this part of our cosmic neighborhood. After all, he discovered Eris, an icy world more massive than Pluto that proved our old friend wasn't special enough to be considered a full-fledged planet. He also introduced the world to Sedna, a first-of-its-kind dwarf planet that's so far out there, its region of space was long thought to be an empty no man's land. Now Brown has teamed up with Caltech colleague Konstantin Batygin to do a new analysis of oddities in the orbits of small, icy bodies out beyond Neptune. In theirreport published Wednesday in The Astronomical Journal, the researchers say it looks like the orbits are all being affected by the presence of an unseen planet that's about 10 times more massive than Earth — the size astronomers refer to as a super-Earth. "I'm willing to take bets on anyone who's not a believer," says Brown. He thinks existing telescopes have a shot at spotting this mystery planet in just a few years, since this new study points to a band of sky where astronomers should look. What's more, this planet naturally explains why the dwarf planets Sedna and Biden have weird orbits that never let them come in close to the solar system. "This wasn't something we were setting out to explain," says Brown. "This is something that just popped out of the theory." But there was one moment that turned Brown into a believer. Their computer simulations predicted that if this hypothetical planet existed, it would twist the orbits of other small bodies in a certain way. So Brown looked through some old data to see if any icy bodies had been discovered with those kinds of orbits — and, lo and behold, he found five of them. "They're objects that nobody has really explained or tried to explain before," says Brown. "My jaw hit the floor. That just came out of the blue. Being able to make a prediction and having it come true in five minutes is about as fun as it gets in science." Their work suggests how big the planet must be, and more or less where it could be found. Brown has already started looking. He hopes other scientists will too. "I want to know what it's like. I want to see that it's really there," says Brown. "It will hurt when somebody finds it and it's not me — but I assume it's going to happen, and I'm willing to feel that pain." NPR Mind boggling if this proves to be true.