Radio-quiet neutron star 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 and gamma rays. Most detected neutron stars are pulsars, and emit radio-frequency electromagnetic radiation. About 700 radio pulsars are listed in the Princeton catalog, and all but one emit radio waves at the 400 MHz and 1400 MHz frequencies. That exception is Geminga, which is radio quiet at frequencies above 100 MHz, but is a strong emitter of X-rays and gamma rays. In all,
Radio-quiet neutron star their magnetic poles. When the magnetic poles do not lie on the axis of rotation, and cross the line of sight of the observer, one can detect radio emission emitted near the star's magnetic poles. Due to the star's rotation this radiation appears to pulse, colloquially called the "lighthouse effect". Radio-quiet neutron stars may be neutron stars whose magnetic poles do not point towards the Earth during their rotation. The group of radio-quiet neutrons stars informally known as the Magnificent Seven are thought to emit mainly thermal radiation. Possibly some powerful neutron star radio emissions are caused by a positron-electron