Elevator Music 24 presents the 1977 composition Harmonices Mundi, by composer, multi-instrumentalist and software developer Laurie Spiegel (b. 1945, Chicago). Harmonices Mundi, or "The Harmony of the World" employs the eponymous text by sixteenth-century astronomer and mathematician Johannes Kepler that explains planetary motion as approximate to musical harmony. Spiegel's sonification of Kepler's theory was famously chosen by Carl Sagan as the open track for the golden record affixed to the NASA Voyager spacecrafts launched in 1977.
Currently Voyager 1 has traveled farther than any other manmade object sent from Earth, and could the first manmade object to leave the solar system.