Scientists' plans to find out more about how the world began have been dealt a big blow.
They spent years building a massive machine called a Large Hadron Collider (LHC), to recreate what happened at the beginning of the Universe.
And they got REALLY excited when it was fired up for the first time.
But after just 10 days the £5 billion machine broke down, and now the scientists have announced it won't be up and running until next spring!
At first it looked like the experiment, which is said to be the biggest in the world, was going well.
But it ground to a halt last weekend when the machine was damaged by some magnets that weren't working properly.
The LHC is built in a tunnel underground
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 in Geneva were trying 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 happened.
But they can't carry on with the experiment until the machine is repaired, so getting the huge machine up and running will be their priority after the science lab's winter break.