First Minister Rhodri Morgan and Large Hadron Collider project director Dr Lyn Evans joined with the Morriston Orpheus Choir
A male voice choir swapped concert halls for their strangest location yet - the control room of the "Big Bang experiment" in Geneva.
Morriston Orpheus were invited by the Large Hadron Collider's Welsh project director to perform there.
Dr Lyn Evans joined the 100 choristers and First Minister Rhodri Morgan, who is a vice president of the Swansea choir, in performing.
A magnet problem has meant the collider is out of action until spring 2009.
But the choir had no worries over potential instrument failure, as they performed a selection, including Cwm Rhondda.
The internationally-acclaimed choir were visiting Switzerland to perform at a charity fund-raising concert this weekend, when Dr Lyn Evans, the Cynon-Valley born project director of the experiment spotted the opportunity to sign them up.
The multi-billion pound collider experiment was launched in September and was built to smash protons together at huge speeds, recreating conditions moments after the Big Bang.
Engineers are currently working to investigate the problem, which will take some months, but Dr Evans plans to use the choir's performance as a backdrop for a future address to an international audience representing 50 nations.
Dr Evans said: "When I heard the Morriston Orpheus was coming to Geneva I thought it would be excellent if some of the choristers could come and visit our exciting project.
"It is the most sophisticated scientific instrument of our time, and I am really keen to promote the wider benefits of its work to everyone, but especially the First Minister of Wales and other fellow countrymen."
First Minister Rhodri Morgan, who joined the choir at both concerts, said: "There is no greater privilege in the world of science than being invited to visit the Large Hadron Collider - the largest scientific experiment the world has ever seen and certainly one of the most exciting of our time."
The Large Hadron Collider experiment was started last month
He said it promised to be a superb weekend "celebrating the very pinnacle of scientific achievement and Welsh choral excellence."
The choir visited the LHC site on Sunday morning before singing a selection including Nabucco's opera chorus Speed Your Journey.
"We have a multinational repertoire, but we won't be singing Fly Me to The Moon," joked spokesman Clive Williams before the first concert.
He added that theiir musical director would stop short of a rendition of David Bowie's Space Odyssey.
He said: "We are delighted to be the first Welsh male voice choir to visit Cern [the name of the project] to view and perform at the particle collider research facility.
"We are delighted to be involved in this international project and to support such a gifted Welshman and his colleagues.
"It will be a real joy to fly the flag for Wales and it is a privilege to continue in our role as ambassadors for Wales."
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