In the year 2293, the starship USS Helin was proposed to take part in the Operation Retrieve plan from a start point in sector 21290. The Helin's location was noted on a chart listing the locations of planned Starfleet ship locations in a range of sectors from sector 21166 to sector 23094. (TOS movie: The Undiscovered Country) The Operation Retrieve info was a series of charts created as set dressing by the production artists and decorators, and as such was not all distinctly visible on screen.