Astrophysical fluid dynamics she pulls in her arms. These stars gradually slow down over the eons, but those bodies that are still spinning rapidly may emit radiation that from Earth appears to blink on and off as the star spins, like the beam of light from a turning lighthouse. This "pulsing" appearance gives some neutron stars the name pulsars. After spinning for several million years pulsars are drained of their energy and become normal neutron stars. Few of the known existing neutron stars are pulsars. Only about 1,000 pulsars are known to exist, though there may be hundreds of millions of old neutron
Radio-quiet neutron star Star), "INS" (Isolated Neutron Stars). Defined as thermally emitting neutron stars of high magnetic fields, although lower than that of magnetars. Identified in thermal x-rays, and thought to be radio-quiet. Compact Central Objects in Supernova remnants (CCOs in SNRs) are identified as being radio-quiet compact x-ray sources surrounded by supernova remnants. They have thermal emission spectra, and lower magnetic fields than XDINSs and magnetars. Radio-quiet neutron star A radio-quiet neutron star is a neutron star that does not seem to emit radio emissions, but is still visible to Earth through electromagnetic radiation at other parts of the spectrum, particularly x-rays