Voyager Golden Record

The Voyager Golden Record

Cover of the Voyager Golden Record

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 spacecraft 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.

Background

The Voyager 1 and 2 probes are currently the farthest man made objects from Earth. Voyager 1 has reached the "magnetic highway", an area where charged particles come in and out of the solar system. Like their predecessor Pioneer 10 and 11, which featured a simple plaque, both probes were launched by NASA with a message aboard – 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

Contents

Main article: Contents 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-six languages (55 ancient and modern languages, plus Esperanto), 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.

Playback

Explanation of the Voyager record cover diagram, as provided by NASA

In the upper left-hand corner is an easily recognized 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 arithmetic 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 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 ordinary television (in which the picture is a series of horizontal lines). 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 (2⁹) 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.

Materials

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 4.468 billion years. It is possible (e.g. via mass-spectrometry) 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.

The records also had the inscription "To the makers of music – all worlds, all times" hand-etched on its surface. The inscription was located in the "takeout grooves", 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.

Journey

Voyager 1 was launched in 1977, passed the orbit of Pluto in 1990, and left the solar system (in the sense of passing the termination shock) in November 2004. It is now in the Kuiper Belt. In about 40,000 years, it and Voyager 2 will each come to within about 1.8 light-years of two separate stars: Voyager 1 will have approached star Gliese 445, located in the constellation Ophiuchus; and Voyager 2 will have approached star Ross 248, located in the constellation of Andromeda.

In March 2012, Voyager 1 was over 17.9 billion km from the Sun and traveling at a speed of 3.6 AU per year (approximately 61,000 km/h (38,000 mph)), while Voyager 2 was over 14.7 billion km away and moving at about 3.3 AU per year (approximately 56,000 km/h (35,000 mph)).

Voyager 1 has entered the heliosheath, the region beyond the termination shock. The termination shock is where the solar wind, a thin stream of electrically charged gas blowing continuously outward from the Sun, is slowed by pressure from gas between the stars. At the termination shock, the solar wind slows abruptly from its average speed of 300–700 km/s (670,000–1,570,000 mph) and becomes denser and hotter.

Of the eleven instruments carried on Voyager 1, five of them are still operational and continue to send back data today. It is expected that there will be insufficient energy to power any of the instruments beyond 2025. After that, the spacecraft will continue to orbit the Milky Way galaxy indefinitely.

In popular culture

• The motion picture Starman portrayed the Voyager Golden Record as having been located by an extraterrestrial intelligence who subsequently sent one of their own race to investigate intelligent life on Earth (however, in the movie the record is erroneously depicted as including the song "(I Can't Get No) Satisfaction" by The Rolling Stones).
• In a Saturday Night Live segment ("Next Week in Review") in episode 64 of the show's third season, Steve Martin's character, a psychic named Cocuwa, predicts that the cover of Time Magazine for the upcoming week will show the four words "Send more Chuck Berry," which had supposedly been sent from extraterrestrials to Earth the week before.
• In an episode of Pinky and the Brain, Brain changes the design of the Golden Disk so that it shows his and Pinky's body as that of the leaders of Earth. When aliens intercept the disk, they capture Pinky and Brain as pets, thinking them to be the leaders of Earth.
• In the speculative nonfiction series Life After People it is stated that, after a million years of travel in interstellar space, the Voyager probes will be so heavily damaged from micrometeoroid impacts that the disks will likely become unreadable. This process will be dependent on the frequency of particle impacts upon the spacecraft in interstellar space.
• A key plot element of the 1994 science fiction film Without Warning involves an alien race having intercepted Voyager and relaying part of the UN Secretary-General's message back to Earth.
• In the movie Battlefield Earth an alien race finds the voyager probe and are interested in Earth because gold is extremely rare and valuable to them.
• In the popular television series The X-files the disk is mentioned in the first episode of the second season Little Green Men.
• In the Transformers cartoon Beast Wars, one of the discs is a key plot point that sets the series in motion.
• The disc is a plot element of an episode of The West Wing, titled "The Warfare of Genghis Khan".
• In the series 2 episode A Day in the Death, of the Doctor Who spinoff Torchwood, Owen Harper says that he found an alien capsule with beautiful music that he says is a response to the Voyager.
• In the movie Star Trek: The Motion Picture the Voyager probes and their records are a major plot point (however, neither Voyager 1 nor Voyager 2, but a fictitious Voyager 6 probe is the one relevant to the movie's plot) .

Publications

Most of the images used on the record (reproduced in black and white), together with information about its compilation, can be found in the 1978 book Murmurs of Earth: The Voyager Interstellar Record by Carl Sagan, F.D. Drake, Ann Druyan, Timothy Ferris, Jon Lomberg, and Linda Salzman. A CD-ROM version was issued by Warner New Media in 1992. The CD-ROM was the result of Sagan's diligence in obtaining copyright clearances for many of the numerous musical passages and photographs that the original Golden Record contained, to allow for their inclusion in the Warner New Media release. (The copyright owners for the images and music on the actual record signed agreements which only permitted the replay of their works outside of the solar system.)

In July, 1983, BBC Radio 4 broadcast the 45-minute documentary Music from a Small Planet, in which Sagan and Druyan explained the process of selecting music for the record and introduced excerpts.

See also

• Communication with extraterrestrial intelligence
• Pioneer plaque
• Time capsule
• Arecibo message

References

• Originally based on public domain text from the NASA website, where selected images and sounds from the record can be found.

External links

• Official NASA JPL page about the Golden Record
• Multimedia showcase with the contents of the Golden Record
• Web site with all of the images, languages, and sounds on the Record.
• Cosmic Journey: The Voyager Interstellar Mission and Message
• U Iowa website with Termination Shock information

• John Cohen and the Voyager Record from The Celestial Monochord
• Article on Ithaca, NY connections to the Voyager Record, 30th anniversary, page 11
• NYT 30th Anniversary OP-ED article by Timothy Ferris, who supervised the production of the disc
• NPR.org: Voyagers' Records Wait for Alien Ears
• David Munrow and the Voyager Golden Record
• WNYC Radiolab interview with Ann Druyan on her role in the making of the Voyager Record, May 12, 2006
• Smithsonian National Air and Space Museum's Voyager Record Cover
• Interview with Jon Lomberg on Australia's Radio National The Science Show, November 19, 2005