Stellar Aberration Bradley 1727
Aberration isn’t parallax; it’s true of all stars and dependent on latitude.
The MS version uses the HC model above (top) to explain the annual variation in aberration.
It follows Bradley’s formula for the aberration angle alpha – above (bottom).
Alpha ~= v/c * sin(lat)
Here lat is the latitude angle and v is the speed of the Earth with respect to the Sun.. 30 km/s.
The expected view angle in (a) (computed assuming the Earth rotates) is corrected by tilting the telescope by alpha. MS attributes this to the motion of the earth eastward (v in (b)) while the light traverses the telescope at speed c.
There is an obvious –and ignored – conflict here with relativity, for which motion is independent of reference frame, and the required use of the HC system to measure v.
In any other reference system the Bradley formula is invalid, so the HC system MUST be used, an absolute condition contrary to SR.
There’s the logical issue, too, of how the starlight knows to use the Sun at rest, out of all the possible reference systems for aberration…. So anyone who accepts the Bradley derivation must rationally reject relativity.
The Airy test provided physical evidence that refuted Bradley’s theory of aberration due to Earth’s motion.
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