Superman: 1952: The Second Superman
by Dan Swanson, adapted from Superman #119 by Edmund Hamilton and Wayne Boring 
The planet Krypton, that planet of Superman’s birth, perished years ago in a catastrophe. But now, in the vast realms of the universe, there looms up a world that is a near-exact double of perished Krypton. Given a rare opportunity to learn about the Krypton-like planet Xenon, he switches places with his twin from Xenon. But while the young Xenonian Kell Orr plays the part of Superman on Earth, Superman soon discovers the terrible truth that the world of Xenon is doomed, presenting him with the greatest challenge of his life. Can the Man of Steel tamper with mysterious cosmic forces and save the world that was Krypton’s twin before it’s too late?