These stars, if they exist, are thought to start from a
neutron star with a mass that would cause it to collapse into a
black hole if it were not rapidly spinning. Instead, the neutron star spins fast enough so that its
centrifugal force overcomes gravity. This makes the neutron star a typical but doomed
pulsar whose strong
magnetic field radiates energy away and slows its spin. Eventually the weakening centrifugal force is no longer able to halt the pulsar from collapsing into a black hole. At that moment, part of the pulsar's magnetic field outside the black hole is suddenly cut off from its vanished source. This magnetic energy is instantly transformed into a burst of wide spectrum radio energy. As of January 2015, seven radio events detected so far might represent such possible collapses; they are projected to occur every 10 seconds within the observable universe. ==References==