The Voyager Golden Records are phonograph records which were included aboard both Voyager spacecraft, which were launched in 1977. They contain sounds and images selected to portray the diversity of life and culture on Earth, and are intended for any intelligent extraterrestrial life form, or for future humans, who may find them. The Voyager spacecrafts are not heading towards any particular star, but Voyager 1 will be within 1.6 light years of the star Gliese 445, currently in the constellation Camelopardalis, in about 40,000 years.
As the probes are extremely small compared to the vastness of interstellar space, the probability of a space-faring civilization encountering them is very small, especially since the probes will eventually stop emitting any kind of electromagnetic radiation.
Carl Sagan noted that “The spacecraft will be encountered and the record played only if there are advanced space-faring civilizations in interstellar space. But the launching of this ‘bottle’ into the cosmic ‘ocean’ says something very hopeful about life on this planet.” Thus the record is best seen as a time capsule or a symbolic statement more than a serious attempt to communicate with extraterrestrial life.
The Voyager Golden Record
As of 2012, the two Voyager spacecraft became the third and fourth human artifacts to escape entirely from the solar system. Pioneers 10 and 11, which were launched in 1972 and 1973 and preceded Voyager in outstripping the gravitational attraction of the Sun, both carried small metal plaques identifying their time and place of origin for the benefit of any other spacefarers that might find them in the distant future.
With this example before them, NASA placed a more comprehensive message aboard Voyager 1 and 2—a kind of time capsule, intended to communicate a story of our world to extraterrestrials.
This is a present from a small, distant world, a token of our sounds, our science, our images, our music, our thoughts and our feelings. We are attempting to survive our time so we may live into yours. – U.S. President Jimmy Carter
The record is constructed of gold-plated copper. The record’s cover is aluminum and electroplated upon it is an ultra-pure sample of the isotope uranium-238. Uranium-238 has a half-life of 4.51 billion years. It is possible that a civilization that encounters the record will be able to use the ratio of remaining uranium to daughter elements to determine the age of the record.
Cover of the Voyager Golden Record
The contents of the record were selected for NASA by a committee chaired by Carl Sagan of Cornell University. Sagan and his associates assembled 116 images and a variety of natural sounds, such as those made by surf, wind, thunder and animals (including the songs of birds and whales). To this they added musical selections from different cultures and eras, spoken greetings in fifty-five languages, and printed messages from President Jimmy Carter and U.N. Secretary-General Kurt Waldheim.
The collection of images includes many photographs and diagrams both in black and white and color. The first images are of scientific interest, showing mathematical and physical quantities, the solar system and its planets, DNA, and human anatomy and reproduction. Care was taken to include not only pictures of humanity, but also some of animals, insects, plants and landscapes. Images of humanity depict a broad range of cultures. These images show food, architecture, and humans in portraits as well as going about their day to day lives. Many pictures are annotated with one or more indications of scales of time, size, or mass. Some images contain indications of chemical composition. All measures used on the pictures are defined in the first few images using physical references that are likely to be consistent anywhere in the universe.
The musical selection is also varied, featuring artists such as Beethoven, Guan Pinghu, Mozart, Stravinsky, Blind Willie Johnson, Chuck Berry and Kesarbai Kerkar.
After NASA had received criticism over the nudity on the Pioneer plaque (line drawings of a naked man and woman), the agency chose not to allow Sagan and his colleagues to include a photograph of a nude man and woman on the record. Instead, only a silhouette of the couple was included.
The pulsar map and hydrogen molecule diagram are shared in common with the Pioneer plaque.
The 116 images are encoded in analogue form and composed of 512 vertical lines. The remainder of the record is audio, designed to be played at 16⅔ revolutions per minute.
Here is the list of all the pictures in the Golden Record: