Communicating with Aliens
Photograph of Pioneer 10's plaque, which features a design engraved into a gold-anodized aluminum plate, 152 by 229 millimeters (6 by 9 inches). The Pioneer 11 plaque is identical.Credit (image and some text): designed by Carl Sagan and Frank Drake; artwork prepared by Linda Salzman Sagan; photograph by NASA Ames Research Center (NASA-ARC) [link]
The Pioneer plaque deciphered
Annotated illustration of the Pioneer plaque.Credit: vectorized in CorelDRAW from NASA image GPN-2000-001623; vectors by Oona Räisänen (Mysid; Wikimedia Commons) [link]; designed by Carl Sagan & Frank Drake; artwork by Linda Salzman Sagan; annotated by D. W. Hoard (2019)
“…a present from a small, distant world…”
The Voyager Golden Record
Outside case of the Voyager Golden Record. The diagrams at the bottom are the same hydrogen spin-flip calibration for physical units and pulsar map to our Solar System from the Pioneer plaques. The other diagrams contain basic instructions for decoding the sounds and images from the record.Credit: NASA [link]
The contents of the golden records were selected for NASA by a committee chaired by Carl Sagan. Dr. Sagan and his associates assembled 115 images and a variety of natural sounds, such as those made by surf, wind and thunder, birds, whales, and other animals. To this they added musical selections from different cultures and eras, and spoken greetings from Earth-people in fifty-five languages, and printed messages from U.S. President Carter and U.N. Secretary General Waldheim.
The Arecibo Message
Numbers 1-10 in binary format.
Numbers 1, 6, 7, 8, 15 in binary.
Formulas for DNA nucleotides using atomic numbers.
The DNA double helix (blue) and the approximate number of nucleotides in binary (white).
Shape of a human (red, middle).
Map of our Solar System.
Diagram of the Arecibo Radio Telescope that was used to send this message; the “M” shows that it is a reflecting telescope (purple).
The Altair Message
Waiting for contact
Closeup front view of one antenna of the Allen Telescope Array, a radio telescope for combined radio astronomy and SETI (Search for Extraterrestrial Intelligence) research, located outside San Francisco. Note the person near the telescope base for scale.Credit: Colby Gutierrez-Kraybill, CC BY 3.0 [link]