Don't Blame 'Planet Nine' for Earth's Mass Extinctions

Some scientists have suggested that a big undiscovered body lying on the far outer reaches of the solar system could be responsible for many of the mass extinction events throughout Earth's history, by shaking up the distant comet repository known as the Oort Cloud and sending some its denizens screaming toward our planet. "I suspect it has something like zero effect on us," said Mike Brown of the California Institute of Technology (Caltech) in Pasadena. Brown and lead author Konstantin Batygin,