Reply #9: 'May' be larger than Pluto [View All]

When Pluto was first discovered in 1930, it was believed to be far larger than it turned out to be. It took 40-50 years to figure out how small it really was.

Still, until now, no other body in the Solar System has been found that orbited the Sun and was roughly equivalent in size. Even the largest new asteroids were several times smaller than Pluto, I believe.

This doesn't 'redefine' the Solar System. The boundary between what is called a planet, and what is called an asteroid is completely arbitrary, really. Perhaps this new discovery will mess with the arbitrary dividing line, but that is about it. So we'll either have 10 'planets' or just 8. I think eliminating Pluto as an official planet is a cleaner solution.

Pluto is more a 'planet' by tradition than by anything else.

--Peter