Xenon

Xenon was the native planet of the metamorphic Whifferdills. Frobisher was born on Xenon. It was located in Mutter's Spiral. (COMIC: Voyager) The Fourth Doctor's companion Milena was born on the planet, and her father (the leader of the planet) knew the Doctor. (PROSE: Milena)

Behind the scenes

 * There is also a planet called Xenon in the computer game series "".