Actually it’s PSR B1919+2, a pulsar with a period of 1.3373 seconds and a pulse width of 0.04 second. It was the first radio pulsar discovered (in July 1967 by Jocelyn Bell Burnell). The original designation of this pulsar was CP 1919 and it is also known as PSR J1921+2153. It is located in the constellation of Vulpecula.
The British post-punk band Joy Division used an image of CP 1919’s radio pulses on the cover of their debut album, Unknown Pleasures.