same place of reference
"In April 1887, Morely wrote his father that he and Michelson had begun a new experiment, the purpose of which was "to see if light travels with the same velocity in all directions." They also hoped to learn from the experiment the speed of the Earth in orbit and in movement with the solar system; whether the ether was moving or stationary; and, most important to Michelson, some clear proof of the ether's actual existence, with which to confront skeptics. [Take two] identical interferometers, one stationary somewhere in outer space, and one in motion with the Earth. The problem was to find the difference in the paths of light traversing these two instruments."
so if their experiment Failed. What does that prove?
"In April 1887, Morely wrote his father that he and Michelson had begun a new experiment, the purpose of which was "to see if light travels with the same velocity in all directions." They also hoped to learn from the experiment the speed of the Earth in orbit and in movement with the solar system; whether the ether was moving or stationary; and, most important to Michelson, some clear proof of the ether's actual existence, with which to confront skeptics. [Take two] identical interferometers, one stationary somewhere in outer space, and one in motion with the Earth. The problem was to find the difference in the paths of light traversing these two instruments."
so if their experiment Failed. What does that prove?