“In space, no one can hear you scream.” The physics of sound production, the anatomical mechanics of human sound reception, and the lack of any medium to carry the sound waves, tell us why this is the case. Yet this tagline from the Alien film franchise still provides pause, because the fictional worlds humans create about outer space tend to be very noisy places. While the majority of these sounds originate from the all-too-human produced pieces of spacecraft technology, the otherworldly sounds created to “auralize” these fictional worlds propel the imagination. When we encounter such sounds produced by planetary and other celestial bodies, then we come face-to-face, or rather, ear-to-sound wave with an extensive realm of possible sounds that exist alongside and beyond human sound perception. Such is the case with a particular comet being tracked by the European Space Agency (ESA) since early 2004, when the mission known as Rosetta was launched.
Focused on efforts to soft land a spacecraft on this comet, the Rosetta mission made an intriguing discovery in August 2014: Comet 67P/Churyumov-Gerasimenko (67P/C-G, for short) was emitting a low-frequency range of electromagnetic waves inaudible to the human ear. After increasing the frequencies 10,000 times to allow for human reception, the resultant sound composition picked up by the spacecraft’s instruments could easily be imagined as the vocalization of some new sentient life form wending its way through the oceanic vacuum of outer space. While these sounds are theorized to be the result of oscillations in the magnetic field around the comet as it interacts with the solar wind, the imaginative potential provided by this discovery offers one unique way to rethink knowledge frameworks that originate apart from the human. This celestial body and its song point to the importance of sound for analysis of phenomena external to human-based experience.
In disclosing the possibility of compositional sound originating outside human experience, this sonic discovery points to a whole new set of questions and understandings about how the world and universe work and interrelate. Whether we think of these electromagnetic frequencies as a random set of oscillations dispersing into the vast emptiness of outer space, or whether we interpret them as patterns of communication occurring outside of human spatial and perceptual awareness, they provide a compelling set of possibilities toward understanding both the limitations of human sound perception, and the limitlessness of nonhuman and object-based sound production.
Sound has played a unique role within space exploration through its use in representing both the idea of humankind and life on Earth as mediated via human epistemological lenses for an unknown, but imagined, interstellar audience. Now in its 37th year, NASA’s Voyager mission launched twin spacecraft in August and September 1977 for purposes of detailed flyby studies of Jupiter and Saturn and their two largest moons, Io and Titan. After successfully extending the mission of Voyager 2 to include pioneering studies of Neptune and Uranus, in 1990 both spacecraft officially embarked on their current mission of exploring interstellar space beyond our own solar system. That both Voyager spacecraft carry a golden phonograph containing images, music and sounds showcasing the diversity of life on Earth provides an interesting counterpoint to the low-frequency sonic output of comet 67P/C-G.
Accompanying the assortment of genre-based and traditional music from around the globe, this golden record also includes acoustic ecological sounds produced by the Earth’s complex interwoven system of spheres ‒ the biosphere, hydrosphere, lithosphere, atmosphere, and cryosphere. Alongside bird and whale song, cricket chirps and frog calls, and the sounds of thunderstorms, earthquakes, wind and rain, we also hear the sounds of the Anthropocene. These sounds range from human biological to human cultural sounds, revealing for an extraterrestrial listener what curator Carl Sagan and his team of collaborators believed to be uniquely human sounds: the beat of the human heart, laughter, the sounds of mother and child, the diversity of the globe’s languages captured in 55 greetings to the universe, and the ingenuity of human invention and human advancement with the sounds of early tools, Morse Code, a horse and cart, automobile, train, and airplane. This sound archive of human life and civilization on Earth is very much an imaginative product of human agency, an idea that denotes the capacity of human beings to act within any given environment or network of relationships, and one that commonly takes humans’ relationships with nonhuman and, at times, non-sentient counterparts for granted. In the arrangement of sounds chosen for inclusion on the Voyager golden record we can clearly see the importance placed on how these sounds contextualize and support human agency as the central player in the development of knowledge. Rather than being understood as providing other models of experience, the sounds of the Earth’s interwoven system of spheres serve as background material for humankind’s continued pursuit of that knowledge.
However, the song produced by comet 67P/C-G serves as an additional example for the importance of these other models of experience as responses to the Anthropocene, the critical idea that links the impact of human beings to multiple system-wide changes on a planetary level. The alien materiality of the comet’s composition, the long trajectory it participates in across space and time, and the low frequency waves it produces across that traverse all call attention to the limits of our knowledge, and the limits of our experience. When expanded beyond the specifics of comet 67P/C-G, the sonic realm allows us to rethink the very limits of human resilience alongside the nonhuman. The delicate set of entanglements we share with plants, animals, geologies and atmospheres, and with other humans, necessitates that we also continually open our sonic imaginations to those entanglements within and beyond the human.
Author: Daniel Gilfillan
Originally written for KSEVT Space Sight.