"Our place in the universe may be a lot more special than many experts have assumed, new evidence suggests.
Scientists simulating the formation of planetary systems have discovered there is nothing average about the Solar System.
The Earth, and its inhabitants, exist in a peaceful system where planets have near circular orbits and do not interfere with each other.

This is not true of other star systems, where orbits are elongated and unstable.
The new computer simulations, using data from 300 planets orbiting other "suns", show that the Solar System owes its quiet life to early conditions being "just right".
If they had been even slightly different, unpleasant things might have happened - like planets being thrown into the sun or jettisoned into deep space.

Before the discovery of "exoplanets" in the early 1990s astronomers had no reason to think the Solar System was unusual.

Professor Frederic Rasio, from Northwestern University in Evanston, Illinois, US, said: "We now know that these other planetary systems don't look like the Solar System at all. The shapes of the exoplanets' orbits are elongated, not nice and circular.

"Planets are not where we expect them to be. Many giant planets similar to Jupiter, known as 'hot Jupiters', are so close to the star they have orbits of mere days.
"Clearly we needed to start afresh in explaining planetary formation and this greater variety of planets we now see.""