Name: Jax-Ur
Universe: Earth-1
Base of Operations: Phantom Zone
First Appearance: Adventure Comics #289

History:
Jax-Ur was the first criminal to be exiled to the Phantom Zone. A former co-worker with Jor-El at Krypton's Space Center, Jax-Ur created a nuclear missile with which he planned to destroy a huge meteor as a test. Instead, it went astray and struck Wegthor, one of Krypton's moons, which had been colonized. For this, Jax was sent to the Zone for life – but with hope of parole.