In 1977, NASA launched the Voyager Golden Record to represent human culture to potential extraterrestrial life. Among classical masterworks by Bach and Beethoven was "Chakrulo," a dramatic polyphonic folk song from the nation of Georgia. Georgian polyphonic singing features three or four independent melodic lines interlocking without instruments, an ancient musical tradition that developed independently of Western European harmony and predates Christianity in the region.
A Golden Archive for Deep Space
In the late summer of 1977, NASA launched two robotic probes, Voyager 1 and Voyager 2, on an unprecedented grand tour of the outer planets. Recognizing that these spacecraft were destined to eventually leave the solar system and wander the interstellar void indefinitely, the mission organizers decided to include a cultural message from Earth. The result was the Voyager Golden Record, a 12-inch gold-plated copper phonograph disc designed to preserve a snapshot of human civilization and terrestrial life for any extraterrestrial intelligence that might encounter it in the distant future.
The project was led by a committee chaired by astronomer Carl Sagan, who assembled a team to select sounds, spoken greetings in dozens of languages, diagrams, photographs, and a wide-ranging collection of music. Rather than focusing exclusively on the celebrated classical canon of Western Europe, the curation team sought to reflect the sonic diversity of the entire planet. Alongside works by Johann Sebastian Bach, Ludwig van Beethoven, and Wolfgang Amadeus Mozart, the disc featured traditional music from diverse societies across Asia, Africa, the Americas, and Eastern Europe.
Among these non-Western entries was a remarkable choral recording from the nation of Georgia: a traditional folk song known as "Chakrulo." Placed on the disc alongside blues pioneer Blind Willie Johnson, rock-and-roll innovator Chuck Berry, and traditional gamelan music from Java, this piece introduced deep space to one of the oldest and most complex vocal traditions in human history.
"Chakrulo" originates in Kakheti, a historic region of eastern Georgia renowned for its rich agricultural landscape and distinct choral singing traditions. Functionally, it is classified as a table song, or "mravalzhamieri," traditionally performed at elaborate communal banquets known as supras. Despite its setting at social gatherings, "Chakrulo" is far from casual background music; it is a dramatic, ceremonial epic that blends festive celebration with themes of historical resistance, peasant defiance against oppressive rulers, and collective valor.
The performance of "Chakrulo" relies entirely on the human voice without instrumental accompaniment. The piece is structured around three distinct vocal layers that operate with complete independence yet create a coherent harmonic whole. At the foundation lies a slow, resonant choral bass that establishes an anchored harmonic drone. Moving above this base are two distinct solo tenor voices that alternate and intertwine, producing intense vocal counterpoint characterized by wide melodic leaps, intricate ornamentation, and dramatic vocalized exclamations.
The interplay between the two soloists requires extraordinary technical skill and precise vocal control. One soloist typically carries a declamatory, highly expressive narrative line, while the other introduces sweeping, yodel-like ornaments and high sustained calls. The voices clash in intentional dissonances before resolving into open, resonant intervals, generating an acoustic tension that mirrors the song's dramatic themes of struggle and solidarity.
Polyphony Born Outside the Western Canon
The inclusion of "Chakrulo" on the Golden Record highlighted an ancient musical reality that often surprises listeners accustomed to standard music history: polyphony did not originate solely within the cathedrals and courts of medieval Europe. The Georgian tradition of polyphonic singing developed entirely independently of the Western European contrapuntal systems that eventually produced the fugues of Bach and the symphonies of Beethoven.
Historical and musicological evidence indicates that Georgian polyphony predates the arrival of Christianity in the Caucasus region during the fourth century. Before it was integrated into Christian liturgical services, this multi-part singing style flourished as a secular and ritualistic practice tied to agricultural labor, hunting, healing rituals, and warfare. The survival of these interlocking vocal techniques over millennia occurred primarily through oral tradition, passed from generation to generation without the aid of formal musical notation.
Unlike Western classical harmony, which came to rely heavily on equal temperament and standardized major and minor chord structures, traditional Georgian polyphony utilizes non-standard tuning systems, neutral thirds, and distinctive cadences based on parallel fifths and unisons. This gives songs like "Chakrulo" a raw, resonant acoustic signature that feels simultaneously ancient and radically modern to outside listeners.
Curating Humanity on a Single Disc
The selection of music for the Golden Record involved difficult decisions, as Sagan's committee had limited space on the physical discs to represent thousands of years of global musical development. The team aimed to avoid a purely eurocentric perspective, balancing famous orchestral compositions with field recordings that demonstrated the breadth of human vocal techniques and acoustic ingenuity.
The curated playlist contained 27 musical tracks representing cultures across the globe, including Navajo chants, Japanese shakuhachi flute music, Pygmy vocal polyphony from Central Africa, Peruvian panpipe melodies, and classical traditions from India and China. In this curated lineup, "Chakrulo" served as a powerful testament to the capabilities of the unaccompanied human ensemble, proving how complex harmonic structures could emerge from folk traditions rooted in local topography and community life.
The inclusion of a Georgian choral piece also stood out in the geopolitical climate of 1977. At the time of the Voyager launches, Georgia was a constituent republic of the Soviet Union. Selecting "Chakrulo" allowed the committee to celebrate a distinct regional culture from within the Soviet sphere, prioritizing deep cultural heritage over the political tensions of the ongoing Cold War.
A Message Wandering the Interstellar Void
Both Voyager spacecraft have since crossed the heliopause—the boundary where the sun's solar wind gives way to the interstellar medium—making them the most distant human-made objects in existence. As they travel through interstellar space, their power sources are slowly depleting, but the physical Golden Records attached to their exteriors are protected by aluminum jackets and are expected to survive for hundreds of millions of years in the vacuum of space.
Whether or not an extraterrestrial intelligence ever intercepts the probes and decodes the audio grooves, the Golden Record remains a defining artifact of humanity's self-conception in the late twentieth century. Through "Chakrulo," the intricate harmonies developed in the valleys of the Caucasus have become a permanent part of the cosmos, carrying Earth's collective musical memory far beyond the lifespan of the civilization that launched it.
Key takeaways
•"Chakrulo" is a traditional polyphonic choral folk song from the Kakheti region of Georgia, selected by NASA for the 1977 Voyager Golden Record.
•Georgian polyphony developed entirely independently of Western European classical harmony and predates the arrival of Christianity in the region.
•The song features complex, unaccompanied vocal counterpoint, combining a choral bass drone with two intertwining solo tenor parts.
•The Voyager records carry the song into interstellar space, designed to preserve examples of Earth's acoustic diversity for millions of years.