Scientists gather for the announcement from CERN on the Higgs Boson particle.
The Higgs Boson is a hypothetical particle which is predicted to exist by particle physics. The Higgs boson explains why other particles in the universe have mass, but scientists are not sure if it exists - or if it it exists exactly as they expect.
That is why they have been trying to find the Higgs Boson. At the CERN Large Hadron Collider they hope to create an experiment where it can be measured, the experiment has been likened to re-creating the Big Bang.
In December last year scientists at the Large Hadron Collider (LHC) in Cern revealed they had caught a first tantalising glimpse of the Higgs.
They have since sifted through vast quantities of data from innumerable high energy collisions in an effort to reduce the odds of being wrong.
A statistical standard of proof known as "five sigma" would be the ultimate confirmation of a discovery. In this case, the chances of a mistake are one in a million.
Scientists at Cern, the European Organisation for Nuclear Research in Geneva, are likely to announce a significant step further towards the five sigma goal.
Possibly, they might even be at "four sigma", a hair's-breadth away from having the Higgs in their grasp. In that case the final "discovery" of the Higgs particle will be virtually a foregone conclusion.
– Cern's director for research and computing, Sergio Bertolucci
We now have more than double the data we had last year. That should be enough to see whether the trends we were seeing in the 2011 data are still there, or whether they have gone away. It's a very exciting time."
The hunt for the fabled "God particle" that lends mass to matter and holds the universe together could soon be over.
Scientists giving a progress report on the search today are expected to say they are almost at the point of confirming the existence of the Higgs boson.
Almost, but not quite. The process of proving the Higgs is real is a gradual one, similar to getting closer to a familiar face seen from afar.