Luminiferous aether became the answer. It was the medium that light travelled through, an invisible substance all around us that couldn't be felt the way air could, but just existed. It was the stuff that waved when light moved, the same way that air waved when sound moved. With that, scientists went on to measure the "aether wind." Michael Fowler from the University of Virginia explains that, under the assumption of the aether, the Earth moves through it while orbiting the sun. Therefore, the aether should be felt rushing past the Earth (like if you ran your hand through water), and ligh...