Scientists hope to gain an insight into the so-called "God particle" [AFP]

The excitement in the air was palpable this morning.

We arrived at the laboratories of the European Organisation for Nuclear Research (Cern), just outside Geneva in Switzerland, to witness what some believe is the most important scientific moment of the new century.

At 9.30am local time (0730 GMT) researchers turned on the Large Hadron Collider, firing a beam of protons for the first time around this 27km ring.

There was a countdown clock on a giant screen, and thousands of scientists cramming around computer screens. They hoped it would work, and it did.

There was rapturous applause the moment the first beam was launched and more every time the beam passed through each of the eight crucial sectors. Almost an hour later saw the biggest reaction - when the proton beam completed its first full loop. Soon there'll be beams heading in both directions and eventually they’ll be crashing into each other.

It is rare that we get to witness important moments in history, but today there was a real sense of that happening.

I spoke to Dr Archana Sharma, a Cern physicist, who could barely contain her excitement. She believes this moment was on par with the discovery that the earth was round and that gravity exists. She was relieved too, that the system seems to be working.

Scientific discovery

From the moment they saw the first tiny pulse of light on a screen this morning, the 9,000 scientists here knew they were seeing the start of a process that could unlock the secrets of the universe.

John Ellis, another Cern physicist, felt relief: "Overnight we had some difficulties with the cooling system, with some of the electrical system and so on, so I think everybody was on tenter hooks this morning, so I think its just fantastic that the guys could get it to work so quickly."

As science projects go, this is as big as it gets. They've spent $8bn since 1994 building the structure 100 metres under the French Swiss border. The aim is to shoot the proton beams at almost the speed of light in opposing directions, crashing into each other to create the mother of all experiments.

The collisions occurring inside the giant machines will hopefully recreate the same conditions that existed in the first trillionth of a second after the big bang.

Critics of this project believe it could all go wrong, causing a black hole to open up, swallowing the planet and life as we know it. But the scientists at Cern are confident it will go according to plan.

Over the coming weeks and months, the experiment will enter a more complex phase, whereby at four points along the route the protons will intersect. It's the important bit of the experiment. When they smash together scientists hope the matter that's created could help them understand how the universe came into existence.

They hope eventually to gain more insight into the Higgs boson, the so-called "God particle" which could explain why some matter has mass, while other matter does not. Understanding that, could revolutionise the way we understand the universe.

For the Physics boffins who have traveled to Gevena from across the world to witness this, today was an exciting moment, but they will have to wait months, possibly even years until the results begin to emerge.