SCIENTISTS have undertaken a project to find out if life on other planets could be 'sparked' into being by a bolt of lightning.

A team at St Andrews University examined how lightning may behave on planets far from the solar system when it forms in clouds on alien worlds.

The researchers, from the University's LEAP (Life Electricity Atmosphere Planets) group at the School of Physics & Astronomy hope to find out the part it may have played in forming life on earth.

Atmospheric electrical discharges have been noted on planets other than Earth such as Jupiter, Uranus and Neptune, but it is likely that lightning occurs outside the solar system.

By building a discharge model team leader Dr Christiane Helling and her group were able to study the large-scale properties of lightning in cloud-forming atmospheres far from earth, and work out how much energy would be injected by a strike.

They found that strikes are more energetic in brown dwarfs, balls of gas sometimes called 'failed stars', than in giant gas planets.

Dr Helling said: "We have started to investigate how an extrasolar atmosphere changes its chemical composition due to the energy released by lightning, which in turn increases the atmospheric temperature considerably.

"There is now the possibility of working out whether large-scale lightning discharges could occur in gemstone clouds, how big they could grow, and as a result whether such events could have triggered the formation of prebiotic molecules responsible for the origin of life."