Relative and Absolute Stellar Aberration

Abstract

If we talk about Stellar Aberration, then we think of the form of Stellar Aberration that was first discovered
and explained by Bradley. In addition to Bradley's Stellar Aberration, which can also be defined
as Relative Stellar Aberration, we will define Absolute Stellar Aberration based on just one measurement.
Here after we will refer to the Absolute Stellar Aberration as $ASA$. We will try to explain in a few words why
it is necessary to measure and interpret Stellar Aberration in this way. Suppose we performed two measurements
of the Doppler Effect within six months. If we don't know the results of those measurements,
but only difference between them, then we cannot determine the radial velocities with which the observer
moves with respect to the star. We will prove that similar reasoning can be applied in the case of
Stellar Aberration as defined by Bradley. Knowing only the difference between the two measurements
of the Stellar Aberration, we are not able to determine the transverse velocities the observer moves
with respect to the line of sight, but only their difference. Using the results of $ASA$ measurements,
we will determine a Reference Inertial Frame and after that derive formulas for
Relative and Absolute Stellar Aberration.