 What is Rolf's new plan when he spots the rocket?
Sisko Rolf's stocky body was a blur of motion as he cut the rocket jets, doused the twin searchlights, and switched over to the audio beams that served so well on the surface when blind flying was in order. Rolf swung the lax controls over hard as the bursts of fire revealed a looming barrier of stone dead ahead, and then he felt the tough skin of the flyer crumple inward. Somehow Rolf found the strength to wrap his fingers around the control levers and snap on a quick burst from the landing rockets. The ship struck; split open like a rotten squash, and Rolf felt himself being flung far outward through thick blackness. "They may have found the sunken seas of Mars," thought Rolf as he moved alertly forward, "water that would give the mining domes new life." Toward this barrier the spinner bore him, and Rolf was content to let it move in that direction—from the heights of the wall he could scout out the country beyond. The spinner had slowed its speed; it seemed to Rolf that he must be falling free in space for a time, but the feeble gravity of the tiny world tugged at him more strongly as he neared the wall. Deftly Rolf nested the spinners again in their pack before he set out toward the heaped-up mass of stone blocks that was the wall.
 He'll be able to distribute water to Mar's colonies, and get out with Tanner and the girl.
 Now that he knows the location of the water, he'll be able to return to grab it for himself.  He'll have a way out of the caverns at last, be able to escape.  He can escape the fighting and leave Tanner and the girl behind.  He'll be able to distribute water to Mar's colonies, and get out with Tanner and the girl.