Hansen's Planet was a Class M planet that had previously been explored by Federation anthropologists by 2267.
Hansen's Planet was home to a species of anthropoids similar to the ones found on Taurus II. Lieutenant Kelowitz was aware of the anthropological lifeforms found on Hansen's Planet and noted their similarities in his report to Captain James T. Kirk following a violent encounter on Taurus II. (TOS: "The Galileo Seven")
Hansen's Planet is in close proximity to the Veridian system, and was seen while Jean-Luc Picard and Data tracked the movement of the Nexus. (Star Trek Generations)