A potential new dwarf planet has been discovered in the outer reaches of the solar system, and its existence poses the greatest challenge yet to the hypothesis that a ninth planet lurks far from the sun.
"We were very excited to discover 2017 OF201 because it was not expected at all," study leader Sihao Cheng of the Institute for Advanced Study in Princeton, told Space.com. "It's very rare to discover an object both large and with an exotic orbit."
