The Large Hadron Collider has smashed protons together for the first time in two years and is ready to go again.
Engineers have made the LHC stronger so scientists can peer into matter using the highest energies we can produce. Nobody knows for sure what we will find at these higher energy levels. We might need a completely new kind of maths to understand it.
This collision was just a test, but I'm excited to see what happens in June when the scientists start using the beams for real experiments.