The unnamed object — the farthest-known object in the solar system — is currently 9 billion miles away from the sun, or about three times Pluto's current distance from the sun. Astronomers do not know its exact size, but its brightness shows that it is at least as large as Pluto and could be up to 1 1/2 times bigger.
Of course, this calls into question whether Pluto should be considered a planet at all.
So do we have ten planets or eight?
