General Chat

plutoid?

"Plutoid" is the word of the moment for astronomers.
It is the new classification that has been sanctioned for the object that was formerly known as the "ninth planet".
It is nearly two years since the International Astronomical Union (IAU) stripped Pluto of its former status as a "proper" planet.
Now an IAU committee, meeting in Oslo, has suggested that small, nearly spherical objects orbiting beyond Neptune should carry the "plutoid" tag.
As astronomy's official nomenclature organisation, the IAU must approve all new names and classifications.
Its decision at the 2006 General Assembly to demote Pluto from "planet" to "dwarf planet" caused an international furore.

Pluto's relegation was felt necessary because new telescope technologies had begun to reveal far-off objects that rivalled the world in size.
Without a new classification, these discoveries raised the prospect that textbooks could soon be talking about 50 or more "planets" in the Solar System.
That prospect proved too much for IAU members who took the historic decision to redefine the Solar System to have just eight major worlds - Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.
They relegated Pluto to a grouping that includes Ceres (the largest asteroid), and Eris, an object slightly larger than Pluto that orbits even further out from the Sun in an icy region known as the Kuiper Belt.

The IAU's Committee on Small Body Nomenclature has now decided that dwarf planets that move beyond Neptune should be placed in a new sub-category, the plutoid.

For full article see:

http://news.bbc.co.uk/1/hi/sci/tech/7449735.stm