On 60 Minutes, CBS correspondent Bill Whitaker interviews Caltech astronomer Mike Brown who says he’s “pretty dead certain” there’s a ninth planet out there. He explains, when you look at the furthest planets including Pluto, “it looks like they’re being pulling off in one direction.” He believes the big thing pulling them is a big planet, which would be the real ninth planet in the solar system. Brown is known as the man who “killed Pluto” as his research demoted the planet to a dwarf planet in 2006.
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When Whitaker asks if there could be some other explanation, Brown says they’ve tried other explanations to try to prove that it wasn’t a planet but “nothing works.” This real ninth planet is approximately 10 times bigger than Earth and 20 times farther away from the sun than Neptune. 60 Minutes airs Sundays at 7pm on CBS.