Michelson-Morley experiment (done in air) is nonsense (クリ)
In air, light is propagated at c/n. So, the result of M-M experiment (done in air) is only natural.
In a book "Theory of Relativity" by Pauli, W 1958, it's written as follows (quoted from English version ; in 1-6). "Rather should one say that for an observer moving with medium, light is propagated as usual with velocity c/n in all directions".
The defined value of speed of light is based on measurements (with wavelength and frequency) done by Evenson et al. in 1973. Error is 1.1 m / s in pramai. Now measuring instrument is separated into a measuring part and a light source part. When one of them is moved at a constant speed higher than above error (in the direction of light path), different value will be obtained.
Light is propagated in two ways (as follows).
1. In outer space, a star light is reflected by a mirror. Speed of incident light is constant relative to aether.
2. In outer space, a star light is reflected by a mirror. Speed of reflected light is constant relative to the mirror (the emission theory).
In two pictures sbove each, speed of light to a moving observer follows Galilean transformation.