Big Bang experiment fired up

Scientists in Switzerland have powered up a huge experiment, which could help solve the mystery of how the world began.

Some people think the universe was formed when tiny particles smashed into each other and joined to make planets.

The experts in Geneva are testing the Big Bang idea by putting particles in an underground tunnel at top speed.

They fired the first beam of particles on Wednesday morning, and say so far their tests are going well.

See pics of the HUGE machine being powered up

A few people have said they are worried about what could happen, but don't worry, most scientists say it's absolutely safe.

The experiment's being carried out in a special machine called a Large Hadron Collider (LHC), which cost five billion pounds to build.

The machine is buried deep underground inside a 17 mile long tunnel, on the border of France and Switzerland.

Scientists during the switch-on

The first beam of tiny particles finished a lap of the tunnel at 9.30 am on Wednesday morning.

When they are whizzing around fast enough, the scientists will smash the particles into each other, to see what happens afterwards.

Scientist Dr James Gillies said: "We are very excited about the project, we hope to learn more about this wonderful universe of ours."