Galileo timing

Galileo runs on Galileo System Time, fixed to an precision of around 10 nanoseconds, which is also required to be kept in strict agreement with the international reference time, Universal Time Coordinated or UTC. This is achieved by continuously comparing GST with the national real time approximations of UTC carried out by  France, Germany, Italy, Spain and Sweden. This process means UTC time measurements can also be made available to users to within an designed accuracy of 26 nanoseconds, although in practice Galileo has been able to do better than this – down to about 5–10 nanoseconds.