Cosmic Call was the name of two sets of interstellar radio messages that were sent from RT-70 in Yevpatoria, Ukraine in 1999 (Cosmic Call 1) and 2003 (Cosmic Call 2) to various nearby stars. The messages were designed with noise-resistant format and characters. [1] [2]
The project was funded by Team Encounter, [3] a Texas-based startup, which went out of business in 2004. [4]
Both transmissions were at ~150 kW, 5.01 GHz (FSK +/-24 kHz). [5]
Each Cosmic Call 1 session had the following structure. The Scientific Part (DDM, BM, AM, and ESM) was sent three times (at 100 bit/s), [6] and the Public Part (PP) was sent once (at 2000 bit/s), [6] according to the following arrangement:
where DDM is the Dutil-Dumas Message, [7] [8] created by Canadian scientists Yvan Dutil and Stéphane Dumas, BM is the Braastad Message, AM is the Arecibo Message, and ESM is the Encounter 2001 Staff Message. [6]
Each Cosmic Call 2 session in 2003 had the following structure:
where DDM2 is modernized DDM (aka Interstellar Rosetta Stone, ISR), BIG is Bilingual Image Glossary. [5] All but the PP were transmitted at 400 bit/s [5]
The ISR was 263,906 bits; BM, 88,687 bits, AM, 1,679 bits; BIG was 12 binary images 121,301 bits; ESM 24,899 bits. Total = 500,472 bits for 53 minutes. PP was 220 megabytes and sent at a rate of 100,000 bit/s for 11 hours total. [5]
The DDM incorrectly gave the neutron mass as 1.67392, instead of the known value of 1.67492. This error was corrected in DDM2.
The messages were sent to the following stars: [9]
| Name | Constellation | Date sent | Arrival date | Message |
|---|---|---|---|---|
| 16 Cyg A | Cygnus | May 24, 1999 | November 2069 | Cosmic Call 1 |
| 15 Sge | Sagitta | June 30, 1999 | February 2057 | Cosmic Call 1 |
| HD 178428 | Sagitta | June 30, 1999 | October 2067 | Cosmic Call 1 |
| Gl 777 | Cygnus | July 1, 1999 | April 2051 | Cosmic Call 1 |
| GJ 49 | Cassiopeia | July 6, 2003 | April 2036 | Cosmic Call 2 |
| GJ 208 | Orion | July 6, 2003 | August 2040 | Cosmic Call 2 |
| 55 Cnc | Cancer | July 6, 2003 | May 2044 | Cosmic Call 2 |
| HD 10307 | Andromeda | July 6, 2003 | September 2044 | Cosmic Call 2 |
| 47 UMa | Ursa Major | July 6, 2003 | May 2049 | Cosmic Call 2 |