The Adventures of Superman (radio) home planet of Krypton is located on the far side of the sun, as opposed to a distant star system as it is in most stories. During the journey to Earth, baby Kal-el grows into an adult and emerges fully grown from his ship after it lands on Earth. He is never adopted by the Kents but immediately begins his superhero career. This was eventually retconned in later episodes to match the narrative of the comic books. This serial introduced the fictional mineral kryptonite, the radiation from which can weaken and even (in some continuities) kill Superman. Aside from giving
Publication history of Superman Superman encountered a fictional cartoonist provided a tongue-in-cheek look at how such work was delegated. The story, which purported on the title page to tell "how comic strips are written and drawn", showed a studio filled with "artists -- stacks of them -- figure men, background specialists, inkers, letterers" as well as script-writers, all devoted to the production of stories about a Superman-like character, while the original creator of the strip was to Superman's consternation kept busy answering his fan mail ("King of the Comic Books", Superman no. 25, 1943). In the early stories, Superman is the only science-fiction element.