magine firing needles across the Atlantic and getting them to collide halfway. That's the technical challenge facing engineers at the Large Hadron Collider today as they prepare to smash together proton beams at the highest-ever recorded energies.
The first attempt to achieve collisions at 7 teraelectronvolts - 3.5 TeV in each beam - began this morning. If successful, the machine will have broken its own world record for collision energy, which was set at 2.36 TeV last December.
Achieving collisions at 7 TeV is a milestone, and marks the official start of the LHC physics programme. Experiments around the machine will probe tens of trillions of high-energy collisions over the next 18 to 24 months.
CERN is broadcasting a live webcast of the event, and will be reporting from the various experiments throughout the day, alongside its Twitter updates.
Some of the experiments, such as Atlas and CMS, are also featuring their own live commentary and blogging.
Finally, the more technically minded can also track the status of the LHC in graphical form.
