3 　Did Dr. Michelson fail? The answer, in fact, is no. A new perspective of this experiment considers that Michelson’s interferometer, fixed to the Earth, was not travelling against the frame of light. The frame of the light was neither the etheric winds nor the sun. The true field through which the light was transmitted was not an empty geometric space, but a macroscopic gravitational field. The gravitational field was not of the sun but of the Earth. Indeed, this is the ‘background for the speed of light’ claimed to have been found. 　Dr. Michelson detected the undisputed fact that the ether is stationary relative to Earth’s gravitational field. Therefore, this experiment was not a failure. Eventually, we should obtain definitive proof of this by detecting the relative speed of light in space. 　2. Theory 　2.1  The substance field 　The above consideration suggests　that light is produced from the impact, heating and interaction of objects. Substances have gravitational, magnetic, electric and other fields to be called ‘Substance-field’. Light can be considered as a vibration formed within the magnetic field. This might be summarized as follows: 　Light transmits at light speed c, through a magnetic field at the microscopic level and a gravitational field at the macroscopic level. 　Then, the velocity of background of light should be given as the sum of vectors of velocities of objects creating the gravitational field normalized by their ratios of Newton's law of universal gravitation. 　However, it is reasonable to argue that light travels in a gravitational field after leaving the infinitesimal microfield. 　It can be assumed that this gravitational field exists along with the movement of all gravitational fields from all objects that are sources of gravity. The field’s travel speed is determined as a composition of all the effective travel speed vectors of these objects. 　Therefore, the background of light speed is certainly not stationary. At a particular place in space, the travelling speed of the gravitational field is specified as the rest frame of light. Facts that clearly exemplify this include those provided by the Michelson–Gale–Pearson experiment*1 conducted on Illinois prairies in 1925. Perhaps it should be referred to as the law of light velocity, as following. 　Next, I describe a calculation model for the background of light speed. 2.2 Specifying the transmission field for light 2.1.1 Composition of gravitational fields and determining the absolute frame 　Figure 2 shows an example of celestial bodies in space with mass m moving at velocity V; the respective values are listed on the right. The circles are auxiliary lines that show the distance from the origin. The direction of the arrow indicates the direction of travel of the celestial body, and the length of the arrow indicates travel speed V.