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Relativistic Beaming

(Doppler Beaming, Doppler Boosting, Headlight Effect)
(directional relativistic effect on light from relativistic speeds)

Relativistic Beaming (or Doppler Beaming or Doppler Boosting or Headlight Effect) is a factor in the apparent Luminosity of an object when it is moving at Relativistic Speed relative to the observer, due to an exaggerated Doppler effect. When an object is moving at relativistic speeds toward or away from you, its Electromagnetic Radiation, in turn, appears brighter or dimmer than would be seen by an observer stationary relative to the same object.

This effects relativistic Jets, e.g., from Quasars and Active Galactic Nuclei, making them appear brighter or dimmer according to the direction of the jets.