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   The velocity of the observer also affects the apparent location
   of a target:  photons arriving at the observer are subject to a
   &quot;raindrop effect&quot; whereby their velocity relative to the observer
   is, using a Newtonian approximation, the photons' velocity
   relative to the solar system barycenter minus the velocity of the
   observer relative to the solar system barycenter. This effect is
   called &quot;stellar aberration.&quot;  Stellar aberration is independ