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Part of the Large Hadron Collider (LHC)
The machine at the heart of a massive experiment to find out more about how the world began, has broken down again - this time, because of a bird.
The Large Hadron Collider, which cost billions of pounds to build, overheated after a piece of bread was dropped onto electrics powering part of the machine.
Scientists think it's most likely to have been dropped by a passing bird.
It's not the first trouble for the Big Bang machine, which first broke just 10 days after being turned on in 2008.
See pics of the LHC machine being powered up
The Large Hadron Collider is housed in a 16-mile tunnel and has been designed to recreate what happened at the beginning of the Universe.
Scientists think the Universe was formed in a huge fireball that produced all the materials that eventually came together to form the stars and the planets.
The experts want to test the Big Bang idea by using the LHC to smash two beams of particles head-on at super-fast speeds, to see what happens.
The first attempt, in September 2008, ground to a halt when an electrical fault damaged some of the machine's powerful magnets.
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