Since its discovery in 1930, Pluto has always occupied a special place in our hearts as the ninth planet in the Solar System. But recent discoveries of new objects in the Sun’s neighbourhood have called into question the definition of a planet. In 2006, the International Astronomical Union established new criteria to define planets and, sadly, Pluto no longer ranked with the big boys. Instead, it was reclassified a dwarf planet, which sparked heated debates and protests among those striving to restore Pluto’s “planet-hood.”