Voyager Golden Record


The Voyager Golden Records are two identical phonograph records, with one copy aboard each of the two Voyager spacecraft launched in 1977. The records contain sounds and data to reconstruct raster scan images selected to portray the diversity of life and culture on Earth, and are intended for any intelligent extraterrestrial life form who may find them. The records are a time capsule.
Although neither Voyager spacecraft is heading toward any particular star, Voyager 1 will pass within 1.6 light-years' distance of the star Gliese 445, currently in the constellation Camelopardalis, in about 40,000 years.
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."

Background

The Voyager 1 probe is currently the farthest human-made object from Earth. Both Voyager 1 and Voyager 2 have reached interstellar space, the region between stars where the galactic plasma is present. Like their predecessors Pioneer 10 and 11, which featured a simple plaque, both Voyager 1 and Voyager 2 were launched by NASA with a message aboard—a kind of time capsule, intended to communicate to extraterrestrials a story of the world of humans on Earth.
While the Pioneer plaques established the precedent, the idea for including information on humanity onboard the Voyagers was the brainchild of John R. Casani, the project manager. He delegated the task to Sagan, who with colleagues Linda Salzman and Frank Drake realized a metal phonograph record with visual information would outlast magnetic tapes in the outer space environment. The budget Casani gave Sagan was $1,500 for six weeks of work ; he stipulated the Record had to be as light as the Pioneer plaque.

Contents

The contents of the record were selected for NASA by a committee chaired by Carl Sagan of Cornell University. The selection of content for the record took almost a year. Sagan and his associates assembled 116 images and a variety of natural sounds, such as those made by surf, wind, thunder and animals. To this they added audio content to represent humanity: spoken greetings in 55 ancient and modern languages, including a spoken greeting in English by U.N. Secretary-General Kurt Waldheim and a greeting by Sagan's six-year-old son, Nick; other human sounds, like footsteps and laughter ; the inspirational message Per aspera ad astra in Morse code; and musical selections from different cultures and eras. The record also includes a printed message from U.S. president Jimmy Carter.
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 constants that are the same across the universe.
The musical selection is also varied, featuring works by composers such as J. S. Bach, Mozart, Beethoven and Stravinsky. The disc also includes music by Guan Pinghu, Blind Willie Johnson, Louis Armstrong, Chuck Berry, Kesarbai Kerkar, Valya Balkanska, Kamil Jalilov, and electronic composer Laurie Spiegel. The selection of music for the record was completed by a team composed of Carl Sagan as project director, Linda Salzman, Frank Drake, Ann Druyan as creative director, artist Jon Lomberg, ethnomusicologists Robert E. Brown and Alan Lomax, Timothy Ferris as producer, and Jimmy Iovine as sound engineer. The inclusion of Berry's "Johnny B. Goode" was controversial, with Lomax claiming that rock music was "adolescent", to which Sagan replied, "There are a lot of adolescents on the planet." It also included the sounds of humpbacked whales from the 1970 album by Roger Payne, Songs of the Humpback Whale.
The Golden Record also carries an hour-long recording of the brainwaves of Ann Druyan, compressed into a minute of audio. During the recording of the brainwaves, Druyan thought of many topics, including Earth's history, civilizations and the problems they face, and what it was like to fall in love.
After NASA had received criticism over the nudity on the Pioneer plaque, 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. However, the record does contain "Diagram of vertebrate evolution", by Jon Lomberg, with drawings of an anatomically correct naked male and naked female, showing external organs. The person waving on the diagram was also changed: on the Pioneer plaque, the man is waving, while on the "Vertebrate evolution" image, the woman is waving.
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 revolutions per minute.
Jimmy Iovine, who was still early in his career as a music producer, served as sound engineer for the project at the recommendation of John Lennon, who was contacted to contribute but was unable to take part.
Sagan's team wanted to include the Beatles 1969 song "Here Comes the Sun" on the record, but the record company EMI, which held the copyrights, declined. In the 1978 book Murmurs of Earth, the failure to secure permission for the song is cited as one of the legal challenges faced by the team compiling the Voyager Golden Record. In the book, Sagan said that the Beatles favoured the idea, but " did not own the copyright, and the legal status of the piece seemed too murky to risk." When asked about the obstacle presented by EMI with regard to "Here Comes the Sun", despite the artists' wishes, Ann Druyan said in 2015: "Yeah, that was one of those cases of having to see the tragedy of our planet. Here's a chance to send a piece of music into the distant future and distant time, and to give it this kind of immortality, and they're worried about money... we got this telegram saying that it will be $50,000 per record for two records, and the entire Voyager record cost $18,000 to produce." However, this was denied in 2017 by Ferris; in his recollection, "Here Comes the Sun" was not seriously considered for inclusion.
In July 2015, NASA uploaded the audio contents of the record to the audio streaming service SoundCloud.

Images

Playback

In the upper left-hand corner of the record cover is a drawing of the phonograph record and the stylus carried with it. The stylus is in the correct position to play the record from the beginning. Written around it in binary notation is the correct time of one rotation of the record, 3.6 seconds, expressed in time units of 0.70 billionths of a second, the time period associated with the radiation emitted or absorbed by a fundamental transition of the hydrogen atom. The drawing indicates that the record should be played from the outside in. Below this drawing is a side view of the record and stylus, with a binary number giving the time to play one side of the record—about an hour.
The information in the upper right-hand portion of the cover is designed to show how pictures are to be constructed from the recorded signals. The top drawing shows the typical signal that occurs at the start of a picture. The picture is made from this signal, which traces the picture as a series of vertical lines, similar to analog television. Picture lines 1, 2 and 3 are noted in binary numbers, and the duration of one of the "picture lines", about 8 milliseconds, is noted. The drawing immediately below shows how these lines are to be drawn vertically, with staggered "interlace" to give the correct picture rendition. Immediately below this is a drawing of an entire picture raster, showing that there are 512 vertical lines in a complete picture. Immediately below this is a replica of the first picture on the record to permit the recipients to verify that they are decoding the signals correctly. A circle was used in this picture to ensure that the recipients use the correct ratio of horizontal to vertical height in picture reconstruction. Color images were represented by three images in sequence, one each for red, green, and blue components of the image. A color image of the spectrum of the sun was included for calibration purposes.
The drawing in the lower left-hand corner of the cover is the pulsar map previously sent as part of the plaques on Pioneers 10 and 11. It shows the location of the Solar System with respect to 14 pulsars, whose precise periods are given. The drawing containing two circles in the lower right-hand corner is a drawing of the hydrogen atom in its two lowest states, with a connecting line and digit 1 to indicate that the time interval associated with the transition from one state to the other is to be used as the fundamental time scale, both for the time given on the cover and in the decoded pictures.

Manufacturing

Blank records were provided by the Pyral S.A. of Créteil, France. CBS Records contracted the JVC Cutting Center in Boulder, Colorado to cut the lacquer masters which were then sent to the James G. Lee record-processing center in Gardena, California to cut and gold-plate eight Voyager records. After the records were plated they were mounted in aluminum containers and delivered to JPL.
The record is a copper disk in diameter plated first with nickel and then gold. 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 4.468 billion years. It is possible that a civilization that encounters the record will be able to use the ratio of remaining uranium to the other elements to determine the age of the record.
The records also had the inscription "To the makers of music – all worlds, all times" hand-etched on its surface. The inscription is located in the dead wax or "run-out groove", an area of the record between the label and playable surface. Since this was not in the original specifications, the record was initially rejected, to be replaced with a blank disc. Sagan later convinced the administrator to include the record as is.