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2012 VP113

Three images, showing dwarf planet 2012 VP113 in red, then green, then blue, were combined to reveal its path across the night sky (Image: Scott S. Sheppard, Carnegie Institution for Science)

2012 VP113 is a dwarf planet, approximately 450 km (280 miles) in diameter, located at the inner margin of the Oort Cloud, some 80 times further from the Sun than the Earth. It is the most distant object known to be orbiting the Sun, at a distance of roughly 12 billion km (7 billion miles), and is only the second object (the other is Sedna) to have been discovered in this far-off region, although a a very large population is suspected to exist here. Believed to be composed of rock and various ices, it has a pinkish hue.

Intriguingly, the pattern of VP113's orbit appears to hint at the existence of another, much larger world – a "super-Earth" more than 10 times the mass of Earth lying much further from the Sun. Astronomer Scott Sheppard, at the Carnegie Institution for Science, Washington DC, who found the new object with colleague Chad Trujillo, said: "If you took a super-Earth and put it a few hundred astronomical units out, the gravity could shepherd this new object into the orbit it has."

Objects orbiting tat the distance of 2012 VP113, in the "inner Oort cloud", are useful as probes of the early Solar System. That's because they lie too far away to be perturbed by the gas giants (Jupiter, Saturn, Uranus, and Neptune), but too close to the Sun to be affected by the gravity of other stars in our galaxy so their orbits and behavior are thought to be almost unchanged since they first formed.

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