A neutron star that rotates rapidly and emits a beam of radiation: Earth telescopes pick up the pulsars as a regular pulse.

Celestial sources that emit pulses of energy at regular intervals, ranging from a few seconds to a few thousandths of a second.

Pulsars are thought to be rapidly rotating neutron stars, which flash at radio and other wavelengths as they spin.

Out of the 500 radio pulsars, twenty are millisecond pulsars or those that are flashing 1,000 times a second.

A pulsar is a neutron star which produces regular pulses of electromagnetic radiation.

The pulses are very short, and are probably a result of synchrotron emission from a beam produced by the object's magnetic field sweeping around like a lighthouse beam.