- For other uses, see Kappa.
In 2267, Kappa's system was first explored by the Federation starship USS Enterprise. The ship was struck by Graktan's experimental planetary defense system, which smothered the ship with an enveloping fungus that shut down communications and engines, leaving the Enterprise helplessly caught in Kappa's gravity well. A Graktan battle cruiser crewed by James T. Kirk, Spock and Graktan leader Lektor pursued the starship to render assistance. They were forced to disable two attacking Themerian raiders before they could reach the Enterprise. Despite the low gravity and high heat, jettisoned water was able to dissolve the fungus, and the starship escaped Kappa's gravity. (TOS comic: "Creeping Death")
- It was unclear why the 2nd, 3rd and 4th planets were designated delta, gamma and beta, rather than use the Greek language letter sequence of Beta, Delta, and Gamma.