The Disturbed Small Planet

Somehow, unaccountably, the Asteroid Medusa had broken orbit and was now plummeting irresistibly toward Earth! A collision, if one occurred, would mean the end of this planet. Drastic action was called for and a drastic plan executed: a spaceship blasted off from Earth to intercept the Asteroid Medusa. Its mission: to detonate an anti-proton bomb upon the run-away body and blast it into oblivion. But only five persons in the world knew how to operate the highly secret and dangerous anti-proton device: Dr. Elefun, Astro Boy, and Doctors Alfa, Beta, and Gama. These last three Doctors - Alfa, Beta, and Ga ma - were serving a prison sentence when they were ordered aboard the spaceship. They were known to be dangerous men, yet so great was the crisis facing Earth that no risk was too great to take. As the spaceship approached Medusa, however, the true nature of the scientist~criminals emerged: they ordered the pilot to turn the ship around and head for coordinates unknown! Also, somehow they had acquired guns. Though Astro Boy was impervious to bullets, Doctor Elefun and the pilot were not. What was Astro Boy to do - resist, and risk the lives of those aboard ship? Or follow orders and jeopardize the planet Earth and its inhabitants?