A star pattern was a configuration of stars as seen from a stationary point.
In 2268, Lieutenant Rahda noticed that the star patterns visible from USS Enterprise were different from each other before and after an explosion, indicating that their position had changed. She estimated that they had been moved 1,000 light years from their former location, after which Spock corrected her, saying it was in fact 990.7 light years. (TOS: "That Which Survives")