Remarkable Ohio


Below is a complete listing of all Ohio Historical Markers. To find a detailed marker listing including text, photographs, and locations, click on a county below. Our listing is updated by the markers program as new markers are installed and older markers are reported damaged or missing.

34-18 The Michelson-Morley Experiment

Side A: The Michelson-Morley Experiment, conducted at Western Reserve University in July 1887, provides the earliest direct evidence that would later support Albert Einstein’s theory of relativity. Albert A. Michelson, professor of physics at the Case School of Applied Sciences, and Edward Morley, professor of chemistry at Western Reserve University, tested the prevailing scientific theory that light waves travel faster downwind and slower against an upwind as they travel through a substance once thought to permeate space called aether. Finding no differences in the velocity of light waves traveling in different directions with respect to Earth’s motion around the sun, the experiment’s results baffled a generation of scientists until Einstein solved the riddle by formulating a new understanding of time and space. In 1907, Michelson, then head of the physics department at the University of Chicago, became the first American scientist to earn the Nobel Prize; he did so in physics.
Side B: Same
Sponsors: The Ohio Bicentennial Commission, The International Paper Company Foundation, and The Ohio Historical Society
Address: 2080 Adelbert Road, 
Location: Case Western Reserve University
Latitude: 41.5043150
Longitude: -81.6069440