Astronomers may have the data they need to prove ‘Planet Nine’ exists

It's been a while now since astronomers began openly discussing the possibility of a ninth planet in our solar system — and no, it's not Pluto.  Now, thanks to a new citizen science effort to detect and identify a mysterious, previously unknown world lurking near the edge of our celestial neighborhood, researchers actually have a handful of possible candidates.Using data from the SkyMapper telescope at the Australian National University, nearly 21,000 citizen volunteers browsed an ast