Cern's Large Hadron Collider (LHC) – the so-called black hole machine – will be out of commission for some months.

An electrical fault has seen a large quantity of liquid helium released into the 17km tunnel, so it's been shut down until at least March next year.
The machine was first tested three weeks ago and had been plagued by problems ever since: first, a group of hackers got into the systems; and now the leak has shut it down for the time being.
Once all tests have been concluded, the LHC will attempt to make atoms collide, giving scientists clues about the atomic make-up of the world.