American astronomer Walter Sydney Adams died #OTD in 1956.
One of Adams' most notable achievements was his collaboration with the astronomer Theodore Dunham, Jr., in the early 20th century. Together, they developed a method for measuring the radial velocities of stars using spectroscopy, which involves analyzing the light emitted or absorbed by celestial objects. This method allowed them to determine the speed at which stars were moving toward or away from Earth.
