A dual set-up based on Bradley's aberration of light, using simultaneously stellar and local light sources
A dual optical set-up is proposed to detect simultaneously the different behavior of light from stellar and local sources, in relation to speed-induced aberration. A small laser is set at the center of the objective lens of a telescope, allowing to record at once the two spots on an array detector. Their positions are recorded during a yearly earth orbit, so stellar aberration can be visualized as a tiny circle. But no aberration has been observed from local sources, hence the laser spot should remain still. The simultaneous recording of both spots allows highlighting their different behavior. Einstein related aberration to the transverse speed between light source and observer, and since for local sources it is null, no aberration ensues. Despite this explanation conforms with the correct result for local sources, it cannot however be retained since stellar aberration does not vary although relative speed differs for each star. Consequently, the null transverse velocity cannot be considered the cause of the null aberration from local sources. A causal approach to this different behavior between stellar and local light is advanced, based on the combined effects of a speed-induced deflection of emitted light rays and a speed-induced aberration upon detection.