Planet (Prisoners of the Kleptons)

An Earth-like planet was the homeworld of the Kleptons. Some time before the 30th century, the planet began moving closer to its sun and became hotter and drier. The Kleptons brought a spaceship crewed by two human astronauts to their world, and shortly afterwards the First Doctor, John and Gillian arrived. They helped the astronauts escaped, then left the planet. (COMIC: Prisoners of the Kleptons)

Millions of Kleptons were killed when their planet moved closer to the sun. (COMIC: The Klepton Parasites)