In 2364, the location of 61 Cygni was labeled in a star chart of a stellar neighborhood with Sol at the center. This chart was stored in the USS Enterprise-D library computer. Later that year, the chart was scanned by Outpost 63. (TNG: "The Naked Now", production art; TNG: "The Last Outpost")
Background information Edit
The star chart naming stars within 20 light years of Sol was drawn by Rick Sternbach for the Star Trek Spaceflight Chronology (p. 77) in the late 1970s. This chart showed Earth commercial and exploration routes after the use of warp drive began. 61 Cygni was the destination on an exploration route.
According to Star Fleet Technical Manual, the United Planets of 61 Cygni was one of the founding members of the Federation. (citation needed • edit) According to The Worlds of the Federation (p. 20), the fifth planet in the system was the homeworld of the Tellarite race.
According to the Star Trek: Star Charts (pp. 19 & 36) and the Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), the two stars of 61 Cygni (Tellar) were K-class stars. An inhabited planet, Tellar Prime (the Tellarite homeworld), orbited 61 Cygni A. The system was located in Sector 007 (Tellar Sector) in the Alpha Quadrant.