Welcome to Plutoids

'Non-planet' Pluto gets new class

"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. Plutoids or haemorrhoids, whatever they call it. This is irrelevant

Alan Stern

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.

More plutoids

In a statement released on Tuesday, the IAU further explained the plutoid definition as celestial bodies that "have sufficient mass for their self-gravity to overcome rigid body forces so that they assume a hydrostatic equilibrium (near-spherical) shape, and that have not cleared [their orbits of debris].

"The two known and named plutoids are Pluto and Eris. It is expected that more plutoids will be named as science progresses and new discoveries are made."

The plutoids will also need to have a minimum brightness.

Ceres will not be considered a plutoid because of its position in the asteroid belt between Mars and Jupiter.

The classification will not placate those incensed by Pluto's demotion.

Alan Stern, a former Nasa space sciences chief and principal investigator on a mission to Pluto, was scathing in his condemnation of the IAU.

"It's just some people in a smoke-filled room who dreamed it up," he told the Associated Press. "Plutoids or haemorrhoids, whatever they call it. This is irrelevant."

"It's just some people in a smoke-filled room who dreamed it up," he told the Associated Press. "Plutoids or haemorrhoids, whatever they call it. This is irrelevant."

Hear Hear.

"A rose by any othe name.....etc.....etc.."

news.bbc.co.uk/2/hi/science/nature/7449735.stm

Alan Stern really needs to get a life already. This whole furore over Pluto is farcical. The thing is not a planet, get over it. Just because some thing is miss-classified for a few decades is no reason to throw the rattle out of the pram when the error is corrected. The science data gathered from Pluto is every bit as valuable regardless of whether Pluto is a planet, a dwarf planet, a plutoid, or some or more of the above.

I don't understand why people get so emotionally tied up in the classification of a ball of dirty ice. The same happened to poor Ceres a few hundred years ago, notice how now one gives a monkeys now. The same will be true of Pluto. If you must be sentimental think of it this way, it has gone from being just one of nine planets to the father or an entire class of object, head of it's own herd instead of the runt of the planetary litter.

Bart.

True.

They "Rename Things" because they do not seem to have the brains to do REAL science. (Like improving on Einstein or something.)

Who gives a monkeys what they call those rocks.

True.

They "Rename Things" because they do not seem to have the brains to do REAL science. (Like improving on Einstein or something.)

Who gives a monkeys what they call those rocks.

There is value in having a proper taxonomy. Sure, astronomy isn't all about taxonomy but that doesn't mean there isn't some needed. As we learn more our taxonomies change. There's no point in getting all sentimental over those changes in taxonomy.

Bart.

well,
Pluto was discovered by an american, the only planet to have been, I believe this is why some people wont let it go, it will in time fade to history and everyone will accept the 8 planet solar system.