Well it's official, the first beam in the Large Hadron Collider at CERN has safely made its way around the 27km tunnel at around 1030 this morning, local time. It was a historic moment, the culmination of over 20 years' work building the biggest experiment the world has seen, and one that many hope will give us a glimpse into the beginnings of the universe and give experimental evidence to long-held theories fundamental to physics.

"It’s a fantastic moment,” said LHC project leader Lyn Evans, “we can now look forward to a new era of understanding about the origins and evolution of the universe.”

Starting up a major new particle accelarator takes much more than just flipping a switch. Thousands of individual elements have to work in harmony and timings have to be synchronized to under a billionth of a second. The second beam was fired at around 2pm local time, and is now making its way around in the opposite direction. Over the next few weeks, as the people at the LHC learn how to drive their new toy, they will steer the two beams, finer than a human hair, into a head-on collision. It will be these collisions that will allow the research programme to begin properly.

Once colliding beams have been established, there will be a period of measurement and calibration for the LHC’s four major experiments, and new results could start to appear in about a year's time. Experiments at the LHC will allow physicists to complete a journey that started with Newton's description of gravity. Gravity acts on mass, but so far science is unable to explain the mechanism that generates mass. Experiments at the LHC will provide the answer. LHC experiments will also try to probe the mysterious dark matter of the universe – visible matter seems to account for just 4% of what must exist, while about a quarter is believed to be dark matter. They will investigate the reason for nature's preference for matter over antimatter, and they will probe matter as it existed at the very beginning of time.

“The LHC is a discovery machine,” said CERN Director General Robert Aymar, “its research programme has the potential to change our view of the Universe profoundly, continuing a tradition of human curiosity that’s as old as mankind itself.”

You can read more about the LHC and the science it is exploring on Plus

• The LHC for dummies
• The physics of elementary particles
• The search for Higgs
• Secrets of the Universe
• Stringent tests
• Time to get packing?
• String theory: from Newton to Einstein and beyond
• Tying it all up

PS. Oh and for the science-scaredy-cats, you can come out from under the bed for now, no black holes have been created as of yet!