## The LHC in numbers

What makes the LHC the biggest particle accelerator in the world? Here are some of the numbers that characterise the LHC, and their equivalents in terms that are easier for us to imagine.

Feature | Number | Equivalent |

Circumference | ~ 27 km | |

Distance covered by beam in 10 hours | ~ 10 billion km | a round trip to Neptune |

Number of times a single proton travels around the ring each second | 11 245 | |

Speed of protons first entering the LHC | 299 732 500 m/s | 99.9998 % of the speed of light |

Speed of protons when they collide | 299 789 760 m/s | 99.9999991 % of the speed of light |

Collision temperature | ~ 10^{16 }°C | over one billion times hotter than the centre of the Sun |

Operating temperature of the superconducting magnets | 1,9 K (-271,3°C) | colder than outer space (which is 2.7 K, or 270.5˚C) |

Amount of helium needed to cool down the facility | ~ 120 t | |

Number of leak-tight pipe junctions necessary to keep the helium cold | ~ 40 000 | |

Volume of the insulating vacuum around the superconducting magnets | ~ 9 000 m^{3} | the volume of the nave of a cathedral |

Pressure inside the beam vacuum pipe | ~ 10^{-13} atm | one tenth of the pressure at the surface of the moon |

Electrical power consumption | ~ 120 MW | twice the power generated by the Rolls Royce 900 engine of an Airbus A380 when the plane is at cruising speed |