A mathematical formula to determine whether objects in space should be classed as a planet could make it easier to identify objects around other stars – but it is bad news for anyone hoping that Pluto could regain its planethood.
In 2006, the International Astronomical Union (IAU) infamously demoted Pluto from planet to dwarf planet status in a controversial decision that left our solar system with eight planets. The IAU cited the fact that Pluto hadn’t cleared its orbit of other debris as a critical factor in…