- See Jansen for other articles with titles that contain, either by relationship or by coincidence, this character's surname.
In 2267, Jansen was one of ten crewmen who joined Kirk and Spock aboard the shuttlecraft NCC-1701/8 to investigate Beton III. Jansen asked Kirk if he expected trouble. Kirk explained that it could be a base for the flying saucer encountered outside the Beton system, and Spock said it was prudent to be prepared. The Collector welcomed the shuttle to land, then shot at it with a cannon, forcing it to crash into a wing of the Collector's museum. When Spock mysteriously disappeared, Kirk had Jansen and the rest of the crew beam back to the ship, out of concern for their safety. (TOS comic: "The Collector")