 The disaster killed 500 inhabitants of the moon and Jax-Ur became the first and only criminal to be banished eternally to the Phantom Zone.This disaster also prompted the Science Council of Krypton to ban space flight completely.A Silver Age Superman was not alone in the survival of Krypton's destruction, being joined by his cousin Supergirl, the Phantom Zone criminals, Beppo the Super-Monkey, Krypto the Superdog, a juvenile delinquent named Dev-Em, the entire population of the city of Kandor, Supergirl's biological parents, and even Superman's biological parents (in hibernation on a space ship - "Superboy" #158 (July 1969)), although it was discovered that they actually died from lethal radiation.