Lesson Four : Pulsars
If the star's core contains less than twenty solar masses of material, its dense core of neutrons will balance the force of gravity and halt its inward collapse. Since it now consists entirely of neutrons, it is called a neutron star.Neutron stars generate intense magnetic fields, which trap electrons and other charged particles. As these they spin, a beam of radiation is formed above each of the star's magnetic poles. These beams sweep the sky, much like a cosmic lighthouse. Spinning, pulsing neutron stars are called pulsars which is short for pulsating radio star. Radio astronomers can learn how fast these stars are spinning, their age, and many other physical properties by observing the frequency of their pulses. Pulsars rotate at rates anywhere from once every 11 seconds to once every two thousands of a second. Their accuracy as a timekeeper rivals that of the best atomic clocks on Earth.
'The Duck' pulsar in radio
NRAO / AUI
NRAO / AUI