 What isn't a reason for bringing the creature back to the ship?
They were something more—and something less—they were, in short, humanity's hopes for survival! The Starship Pandora creaked and groaned as her landing pads settled unevenly in the mucky surface of the ugly world outside. She seemed to be restless to end her fool's errand here, two hundred light years from the waiting hordes on Earth. Earth couldn't turn out enough starmen in the schools, so promising kids were being shipped out for training as cadets on their twelfth birthday. But something had happened to the exploration party fifteen years back, and to the more recent ship under Hennessy that was sent to check up. The Sol-type sun must be rising, since there was a dim light. Even the deep gorge where they'd found Hennessy's carefully buried ship was completely hidden by the fog. Earth had ordered him to detour here, after leaving his load of deep-sleep stored colonists on Official World 71, to check on any sign of Hennessy. If there was no sign in another day or so of what had happened to the men who'd deserted their ship and its equipment, he'd have to report back. Now the three were streaking at fantastic speed to a spot near the ship, to hover excitedly above something that moved there. One, at the front, was stuttering into life, and Gwayne dashed for it as the exit port slid back. At a gesture, the jeep rolled down the ramp, grinding its gears into second as it picked up speed.
 they want revenge for what it did to the cadets
 they want to learn more about him  they want to know why the ship had been hidden  they want to know what happened to Hennessy's group  they want revenge for what it did to the cadets