<P> In 1934 , Walter Baade and Fritz Zwicky proposed the existence of neutron stars , only a year after the discovery of the neutron by Sir James Chadwick . In seeking an explanation for the origin of a supernova , they tentatively proposed that in supernova explosions ordinary stars are turned into stars that consist of extremely closely packed neutrons that they called neutron stars . Baade and Zwicky correctly proposed at that time that the release of the gravitational binding energy of the neutron stars powers the supernova : `` In the supernova process , mass in bulk is annihilated '' . Neutron stars were thought to be too faint to be detectable and little work was done on them until November 1967 , when Franco Pacini pointed out that if the neutron stars were spinning and had large magnetic fields , then electromagnetic waves would be emitted . Unbeknown to him , radio astronomer Antony Hewish and his research assistant Jocelyn Bell at Cambridge were shortly to detect radio pulses from stars that are now believed to be highly magnetized , rapidly spinning neutron stars , known as pulsars . </P>
<P> In 1934 , Walter Baade and Fritz Zwicky proposed the existence of neutron stars , only a year after the discovery of the neutron by Sir James Chadwick . In seeking an explanation for the origin of a supernova , they tentatively proposed that in supernova explosions ordinary stars are turned into stars that consist of extremely closely packed neutrons that they called neutron stars . Baade and Zwicky correctly proposed at that time that the release of the gravitational binding energy of the neutron stars powers the supernova : `` In the supernova process , mass in bulk is annihilated '' . Neutron stars were thought to be too faint to be detectable and little work was done on them until November 1967 , when Franco Pacini pointed out that if the neutron stars were spinning and had large magnetic fields , then electromagnetic waves would be emitted . Unbeknown to him , radio astronomer Antony Hewish and his research assistant Jocelyn Bell at Cambridge were shortly to detect radio pulses from stars that are now believed to be highly magnetized , rapidly spinning neutron stars , known as pulsars . </P>
a spinning neutron star that appears to give off radio waves is called a
a spinning neutron star that appears to give off radio waves is called a
pulsars
pulsars