Huge rock-ice body circles Sun
Astronomers have found a large object orbiting the Sun near Neptune's orbit.
It was discovered on Friday by an automated sky survey project designed to search for threatening asteroids that may be on an Earth impact course.
The object is about 570 km across, making it one of the largest bodies of its kind found in modern times. The new body, made of rock and ice, is designated 2003 VS2. Re-examining past records, astronomers have found it in images taken as far back as 1998.
The object is one of the largest yet found in the Kuiper Belt, a region of space littered with small rocky worlds orbiting the Sun. It was discovered by the automated Near Earth Asteroid Tracking (Neat) project using a large telescope at Mount Palomar in California, US.
It is in a so-called resonance orbit with Neptune. This means that it completes two orbits of the Sun for every three completed by the eighth planet.
Such orbits are stable as they allow the object to approach Neptune's orbit without any possibility of collision. Pluto, currently the most distant true planet, is in such an orbit.
Because of the similarity, 2003 VS2 has been dubbed "Plutino", or "little Pluto". Since the first Kuiper Belt Object was discovered in 1992, several hundred have been found, and many of them are in the Neptune resonance condition, too.
