Assertion: millisecond pulsar | /r/HasProperty | created with high mass density
Facets:
value: from old neutron stars
type: LOCATION
value: extremely
type: DEGREE
value: originally
type: MANNER
Source sentences:
text: It is thought that millisecond pulsars were originally created from old neutron stars with an extremely high mass density and strong magnetic fields; neutron stars form as the inner core of a heavy star explodes – an event called a supernova explosion.