Pluto gets new classification as 'Plutoid'

Richard Gray, Science Correspondent
Last Updated: 6:01pm BST 12/06/2008

Pluto has been stripped of its status as a planet and will now be classified as a "plutoid" - a new category of celestial body

Telegraph science coverage in full
It has taken nearly two years of arguing and negotiations, but astronomers have finally settled on a new way to refer to the former ninth planet.

advertisementIn the revised taxonomy, all small and nearly spherical objects orbiting beyond Neptune, which is now the most distant planet from the sun, will fall under the new tag.

The change was decided by a committee of the International Astronomical Union, which in 2006 took the controversial decision to demote Pluto from planet into a sub-class called dwarf-planets.

The move sparked world-wide furore and many scientists opposed the idea of abandoning a planet that been a feature of the Solar System for around 70 years.

Teachers and text book writers were also left with the task of drastically revising the view the solar system.

Dr Robert Massey, from the Royal Astronomical Society, said: "School books are going to have to be rewritten again after this change.

"From a scientific point of view, it makes sense to bring a more consistent approach to the way we classify objects in the Solar System."

The International Astronomical Union's Executive Committee approved the new Plutoid classification at a meeting in Oslo, Norway this week.

They said that they expected more plutoids to be named as new objects are discovered orbiting around the sun.

There are now two known plutoids in the solar system - Pluto and Eris, a 1,500-mile-wide sphere of rock spotted orbiting beyond Pluto in an icy region known as the Kuiper Belt in 2003.

Eris has since been found to be bigger and heavier than its famous neighbour.

In a statement, the International Astronomical Union said: "Plutoids are celestial bodies in orbit around the sun at a distance greater than that of Neptune that have sufficient mass for their self-gravity to overcome rigid body forces to that they assume a near spherical shape, and that have not cleared the neighbourhood around their orbit."

Astronomers now hope that the decision to classify Pluto as a plutoid will put an end to the debate.

Professor Sir Martin Rees, the Astronomer Royal, said: "The reclassification reflects that Pluto is part of a newly recognised and growing number of objects in the solar system."

The International Astronomical Union has been responsible for naming planetary bodies and their satellites since the early 1900s.

But Alan Stern, a former Nasa space sciences chief and principal investigator on a mission to Pluto, was scathing in his condemnation of the decision. He said: "It's just some people in a smoke-filled room who dreamed it up. Plutoids or haemorrhoids, whatever they call it. This is irrelevant."

http://www.telegraph.co.uk/earth/main.j ... net112.xml

Google Eris AKA Nibiru