Forbidden planet: was Plutoβs 2006 demotion a big mistake?
Since it was stripped of planetary status, Plutoβs defenders have been fighting the decision β and theyβre only getting more passionate
Twenty years ago, Pluto got demoted. After a vote by the International Astronomical Union (IAU) in August 2006, Pluto was relegated from major planet to dwarf planet status. Our solar system dropped from nine planets to eight. At the time, many scientists were unhappy with the decision. Two decades on, the debate is, if anything, even more polarised.
βThe definition of a planet they created, you canβt use it at all,β says Philip Metzger, the director of the Stephen W Hawking Centre for Microgravity Research and Education at the University of Central Florida. βIt makes the definition of a planet completely non-useful in science.β
Continue reading...
Β© Photograph: Universal History Archive/Universal Images Group/Getty Images

Β© Photograph: Universal History Archive/Universal Images Group/Getty Images

Β© Photograph: Universal History Archive/Universal Images Group/Getty Images