Relativistic aberration

Relativistic aberration is the relativistic version of aberration of light for observers who move with velocities close to the speed of light. It can be described by Einstein's special theory of relativity or other relativistic models such as Newtonian emission theory. The effect is independent of the distance between observer and light source.

Suppose, in the reference frame of the observer, the source is moving with speed ${\displaystyle v\,}$ at an angle ${\displaystyle \theta _{s}\,}$ relative to the vector from the observer to the source at the time when the light is emitted. Then the following formula, which was derived by Einstein in 1905, describes the aberration of the light source, ${\displaystyle \theta _{o}\,}$, measured by the observer:

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