An alien species might well find more difficulty in interpreting the audio samples, music, and images contained on the record. There are over 50 greeting messages in different languages. While the specifics of the messages are likely to be uninterpretable, they would at least convey to the listener the diversity of the creatures who created the Voyagers.
Similarly, the musical selections chosen demonstrate a wide range of human musical styles (ranging from works of Beethoven and Stravinsky to those of Chuck Berry, among others). While the lyrics of “Johnny B. Goode” are probably gibberish to an extraterrestrial, the beat and rhythm of the song would convey a tremendous amount to an alien listener.
Of perhaps the greatest importance are the 115
images encoded on the record. The first six images, if decoded properly, provide immense technical data for the reader regarding mathematical definitions, scales and sizes, as well as additional information regarding our location and how to find us. Images of the Sun and its spectrum, as well as some of the planets in our solar system, could help the discoverer of the Voyagers to find us should they decide to pay the Earth a visit. There are also approximately 20 medical and scientific diagrams including the structure of DNA and detailed images of human anatomy. These images could likely be interpreted correctly given their concrete nature.
The Voyager record also contains a plethora of images of humans engaged in a variety of activities (including eating, looking through a microscope, and even going on a spacewalk). While many of these images would be hard to interpret (e.g., a picture of a woman licking an ice cream cone or a photo of a string quartet) the images would at least convey that humans have created a complex civilization with some degree of advanced technology.
The Big Picture
As Marshall McLuhan famously said, “The medium is the message.” While the recipients of the Pioneer plaque or the Voyager record might never understand everything we are trying to convey, the fact that these messages were placed on interstellar spacecraft carry (both for them and for us) a deeper message — that humans created these spacecraft and that we want to tell the universe who we are.