Scientists say they believe they have captured the elusive Higgs Boson particle that gives matter mass.
Professor John Womersley, chief executive of the Science and Technology Facilities Council, told reporters at a London briefing that they had discovered a particle consistent with the Higgs Boson.
Discovery is the important word. That is confirmed. It's a momentous day for science.
There is a strong Welsh connection to the groundbreaking scientific project as Dr Lyn Evans from Aberdare was the project leader.
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Winds are expected to ease this evening and showers will become lighter and more isolated. A drier and brighter day tomorrow.
After nearly six weeks of campaigning the race for Number 10 has reached its final stages.
Polling stations across Wales will open at 7am on Thursday May 7th. Here is a guide on 'how to' and 'how not to' vote.