A pulsar clock is a clock which depends on counting radio pulses emitted by pulsars.
The first pulsar clock in the world was installed in St Catherine's Church, Gdańsk, Poland, in 2011.[1] It was the first clock to count the time using a signal source outside the Solar System, and represents the second type of clock to measure time using a signal source outside the Earth, after sundials. The pulsar clock consists of a radiotelescope with 16 antennas, which receive signals from six designated pulsars. Digital processing of the pulsar signals is done by an FPGA device.[2]
On October 5, 2011, a display showing the exact time of the pulsar clock, as a repeater of Gdańsk's pulsar clock, was installed in the European Parliament in Brussels, Belgium.[3]