Voyagers Golden Record
Attached to each Voyager spacecraft is a gold-plated, copper phonograph record conveying greetings from Earth to civilizations potentially inhabiting nearby exoplanets in our galaxy (plate 6). Though not the first spacecraft to carry salutations from Earth, Voyager is the first to send our voices, music, and photographs. Pioneer 10 and 11 carry a plaque that includes a map of nearby pulsars indicating the Sun’s location in the Milky Way, a schematic of our Solar System, their flight path from the third planet out, and an outline of the Pioneer spacecraft with the outlines of a man and woman standing in the foreground to demonstrate the humans’ shape and comparable size. The male figure has his right hand raised in a sign of greeting. By contrast, Voyager carries much more detailed salutations to potential species that might happen upon the spacecraft.
The idea of attaching greetings from Earth to the Voyager spacecraft apparently was suggested by John Casani, who served as project manager for Voyager from 1975 to 1977. In October 1974, Casani had scribbled on a routine JPL concern and action report: “No plan for sending a message to our extrasolar system neighbors,” as well as the phrase, “Send a message!”34 Casani asked Carl Sagan to coordinate putting together a message. Sagan was a natural choice to head the effort; he and Cornell astronomer Frank Drake had organized development of the Pioneer 10 and 11 plaques. Sagan understood the powerful public impact of a greeting to possible galactic civilizations, eagerly accepted Casani’s mandate, and recruited a group of scientists, professors, and business leaders for the NASA Voyager Record Com – mittee.35 Sagan additionally consulted with science fiction writers Arthur C. Clarke, Robert Heinlein, and Isaac Asimov and gathered a core group of collaborators including Drake, who in 1961 developed an equation for calculating the number of civilizations that might populate the Milky Way, writer Ann Druyan, science writer and professor Timothy Ferris, astronomy-inspired artist Jon Lomberg, and artist Linda Salzman Sagan, who drew the images for the Pioneer plaque. This core group selected the messages, sounds, music, photos, and diagrams now hurtling into the interstellar abyss.
Inscribed in the grooves of the Golden Record is an essay of sounds of Earth; spoken and written greetings; humpback whale song; 115 photographs and diagrams related to nature, science, and human activities; and ninety minutes of music. Murmurs of Earth, an account of the compilation of the interstellar record, reveals the intense deliberation that went into selecting its contents and determining the medium that would best preserve this special envoy from Earth. It was Drake who recommended using the equivalent of a phonograph record that could record sound as well as photographs that would render as television images. Since corrosion does not occur in the vacuum of space, it was calculated that, excepting a direct collision with micrometeoroids or other space debris in our Solar System, the records might remain intact for a billion years. “We felt like we were on the committee for Noah’s Ark, that we were deciding which pieces of music and which sounds of Earth would be given eternal life, really a thousand million years. We took it as a kind of sacred and joyful task,” recalls Druyan, who gathered the audio clips for the record’s twelve-minute sound essay.36
The sound essay begins with a musical rendering of Kepler’s Harmonica Mundi, a mathematical treatise transposed into sound at Bell Telephone Laboratories. “Each frequency represents a planet; the highest pitch represents the motion of Mercury around the Sun as seen from Earth; the lowest frequency represents Jupiter’s orbital motion. . . . The particular segment that appears on the record corresponds to very roughly a century of planetary motion,” explains Druyan. Following this are sounds of the primordial Earth: volcanoes, earthquakes, thunder, and mud pots. To illustrate the evolution of life, ocean surf, rain, and wind are followed by crickets and frogs, then vocalizations by birds, hyena and elephants, and a chimpanzee. Human footsteps, heartbeats, speech, and laughter come next and fade to the sound of fire and of flint being struck by rock to indicate the evolution of tool use. These are followed by a tame dog’s bark, and the clamor produced by sheep herding, blacksmithing, sawing, and agriculture. Next is Morse code tapping out the phrase Ad astra per aspera, which translates as “to the stars through difficulties,” a suggestion by Carl Sagan. To trace the evolution of travel technologies in the twentieth century, the clatter of horse-cart and noise of an automobile segue to an F-111 flyby and the cacophony of a Saturn V liftoff. Concluding the sound-essay are juxtaposed sound files of electromagnetic waves of human brain activity, actually those of Druyan, in case an advanced civilization could read human thoughts, and the radio output of a pulsar, a collapsed star in rapid rotation. As Druyan points out: “My recorded life signs sound a little like recorded radio static from the depths of space. The electrical signatures of a human being and a star seemed, in such recordings, not so different, and symbolized our relatedness and indebtedness to the cosmos.”37
Frank Drake and artist Jon Lomberg were tasked with putting together the Golden Record’s photo essay and selecting images that might make sense to a nonhuman species. Lomberg has sent more of his own art into space than perhaps anyone, having designed the sundial on the Spirit and Opportunity rovers and created the Visions of Mars DVD attached to NASA’s Phoenix Lander as a message to future generations who explore the red planet. For Voyager’s record, Drake and Lomberg compiled 115 photos and diagrams depicting insects, wildlife, ballet dancers, bushman hunters, various landscapes, architecture, an X-ray image of a hand, a radio telescope, the Earth in space, an astronaut space walking on orbit, and even a sunset, chosen in part to illustrate Earth’s beauty and because “the reddening of the light contains information about our atmosphere.”38
The elegantly etched aluminum cover of Voyager’s record indicates how the record is to be played and is Lomberg’s work as well. On the right of the cover are illustrations of the appropriate vertical to horizontal ratio for television images of the photographs and what the first image, a simple circle, should look like. On the left are top-down and side view graphics showing proper placement of the enclosed stylus and the correct rpm speed in binary. The Golden Record is not a conventional 33 1/3 rpm long playing record, as is often claimed. Wanting to include as much data as possible, the committee realized they could embed more music and images if they slowed the playtime to 16 2/3 revolutions per minute. Near the bottom right of the record cover is a diagram to indicate that the transition period of a hydrogen atom between its two lowest states, 0.7 billionths of a second, should be taken as equivalent to 1 in binary code. This is intended to give an accurate speed for spinning the record and for interpreting the pulsar map at the bottom left that depicts our Sun relative to 14 pulsars whose precise periods are notated in binary code.
The committee was adamant about sending music as a form of art, particularly since music expresses a potentially universal, mathematical language. But with only a ninety-minute segment dedicated to music, agonizing decisions had to be made in representing musical genres of the world. Hurtling into the depths of space are selections, among others, of Javanese gamelan, an initiation song from Zaire, Japanese shakuhachi, a raga from India, Melanesian panpipes, panpipes and drum from Peru, a Bulgarian shepherdess song, a Navajo Night Chant, tribal music from New Guinea, Louis Armstrong performing jazz, Chuck Berry playing rock and roll, and classical selections by Mozart, Bach, Stravinsky, and Beethoven. Also included is the Cavatina movement of Beethoven’s String Quartet No. 13 in B Flat, Opus 130, along with an image of sheet music from this selection. It was a piece that Beethoven so cherished he once told a colleague he could cry when thinking of it.39 In researching Beethoven’s Cavatina, Druyan found on the score of an adjacent opus that the composer had written: “What will they think of my music on Uranus? How will they know me?” Beethoven apparently, comments Druyan, “toyed with the thought that his music might leave [our] planet.”40 His intuitive query seems indicative of an artist who saw far beyond his time. For that, and for his deafness, he was often misunderstood or considered eccentric. While reworking the finale rejected by his publisher for the String Quartet No. 13, Beethoven apparently strolled through fields waving his arms, shouting and likely singing, certainly in an attempt to feel since he could not hear, the music playing in his mind and that he found so compelling. So, it seems a perfectly harmonious outcome that Beethoven’s music indeed traveled to Uranus and at this moment, aboard Voyager, is barreling into the pristine interstellar void.