In the race to discover a proposed ninth planet in our solar system, astronomers are conducting the largest, deepest survey for objects beyond Neptune and the Kuiper Belt. Nearly 10 percent of the sky has been explored to date using some of the largest and most advanced telescopes, revealing several never-before-seen objects at extreme distances from the Sun.
The main-belt asteroid (493) Griseldis, that lies between the orbits of Mars and Jupiter, was probably hit by another object last March. The results were reported on 12 November at the 47th Annual Meeting of the Division for Planetary Sciences of the American Astronomical Society near Washington, DC.
Astronomers have found a dwarf planet three times farther away from the Sun than Pluto, making it the most distant known object in the solar system. Designated V774104, the body is 500 to 1000 kilometres in diameter and is currently 15.4 billion kilometres, or 103 astronomical units (AU) from the Sun, but its exact orbit is yet to be determined.