Light, you give birth to the most beautiful !

Till now it is not known, what is the deep-seated parent of a constancy of the light speed, everywhere-whether in Universe it is constant and constant-whether it in general.

What is the light speed? From the stated above (What is the electromagnetic waves  and Squeezing – expansion of ether see) streams, that the light speed is that speed, from which the microzones: the seal and the rarefaction overflow each other in the maternal ether. The microzones fluctuate in this overflow chaotically from one microzone – an ether part to the another.

Perturbation (a jolt) in the maternal ether ("What is the electromagnetic waves" see above) is only the assignment of the direction of the microoscillations with the already available speed "C" -- the assignment of the direction of the wave motion, containing these microzones (and the assignment of its length, amplitude, frequency also).

Thus the light speed is the characteristic parameter of a motion of the most small microelements of ether and this parameter is unclosed outside – in the meso- and the macroCosm of ether by the jolt (the perturbation). This very deeply latent micromotion becomes the accessible to us. 

Why the light speed of different spectrum is constant?  From (Ether microvibration) follows the light speed with an electromagnetic wave of the different length is constant, since it is transmission of oscillations (of "tramble") of ether from the most small (so, the constant) "particle" of ether to other such particle (fig. 18).

Fig. 18. The plan to the proof of constancy of speed of the electromagnetic waves of any length: a - macrowaves; δ - mesowaves. 

It occurs in an electromagnetic wave of any length. So in the mezo (macro) ether wave (i.e. in the electromagnetic wave) the meso (macro)-rarefactions  and the squeezings alternate. The rarefactions and the squeezing alternate too into them (i.e. on the most lowest − the constant microlevel). And since namely they cause the light speed (see above), then the speed of any electromagnetic waves is constant.

Everywhere-whether in Universe the light speed is constant ? As ether in the nearby-limiting to galaxies spaces moves considerably (Formation of galaxies see), then the advance of waves (of the light and the other gamuts) occurs with the various speed in Space. Especially it will be appreciable at the wave motion on and against of the ether current. It leads to that at the wave motion towards to the fluxion of ether the wave reduces the absolute velocity, at the motion in the direction of the fluxion of ether − increases.

In addition, since the density of the maternal ether is different in different macrozones of the Universe (see Universe structure), then in the zones of galaxy clusters the speed of light will be less than into meshes of "honeycombs".

From this it follows, that A.Einstein's known postulate (about the constancy of the light speed in Space) is observed not everywhere and not always.