Almost two years after the International Astronomical Union (IAU) General Assembly demoted Pluto from a “real” planet to the new category of dwarf planets, the IAU, as promised, has decided on a name for trans-Neptunian dwarf planets similar to Pluto. The name “Plutoid” was proposed and accepted by the IAU at its recent meeting in Oslo, Norway. Here’s the definition of a Plutoid: “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 so that they assume a hydrostatic equilibrium (near-spherical) shape, and that have not cleared the neighborhood around their orbit.” 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, for example, when the New Horizons mission arrives at the Kuiper Belt region in 2015.
Ceres, however, although a dwarf planet, is not a Plutoid, as it is located in the asteroid belt between Mars and Jupiter. Astronomers believe that Ceres is the only object of its kind. Therefore, a separate category of Ceres-like dwarf planets may be defined and named at a later date.
The IAU has been responsible for naming planetary bodies and their satellites since the early 1900s, and oversees the assignment of names to surface features on bodies in the Solar System.
The IAU confirmed that in French plutoid is “plutoïde,” and in Spanish “plutoide.”
Sources: PhysOrg, International Astronomical Union
Exploring the Moon poses significant risks, with its extreme environment and hazardous terrain presenting numerous…
Volcanoes are not restricted to the land, there are many undersea versions. One such undersea…
Some binary stars are unusual. They contain a main sequence star like our Sun, while…
11 million years ago, Mars was a frigid, dry, dead world, just like it is…
Uranus is an oddball among the Solar System's planets. While most planets' axis of rotation…
A camera aboard the Mars Express orbiter finds a new lease on life. Sometimes, limitations…