This photo (high-res version) reveals that the stars in the night sky seem to spin around in one direction in space. However, as any textbook will tell you, Earth does the spinning which can be shown in the lab by the rotation of the plane of swing of the Foucault pendulum. But the 19th-century philosopher-physicist Ernst Mach didn't buy this--he believed that the existence of relative motion meant that there was no preferred frame of reference. Mach's ideas--see "Mach's principle"--were part of the inspiration for Einstein's general theory of relativity.
