Photo: Caltech/R. Hurt (IPAC)
US astronomer Dr Michael Brown's theory of a ninth planet, lurking on the very edge of our Solar System, is gaining momentum.
He and his team at the California Institute of Technology have identified a number of asteroids and space rocks which are being pulled into an unusual orbit.
Dr Brown is convinced that it's being caused by Planet Nine - Planet X, as it is sometimes known - and says his new research proves there's a one in a million chance that it's not there.
The only missing piece of the puzzle is locating it.
Dr Michael Brown is the author of How I Killed Pluto and Why It Had It Coming, and as the name suggests, his work is responsible for demoting Pluto from a planet, to a dwarf planet.
