question:  What is so significant about this new area that Rolf is in?
context: 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." He found himself shooting downward into a vast void that glowed softly with a mysterious all-pervading radiance. As the spinner dropped him slowly down into the vast emptiness of the great shining gulf, Rolf could see that a broad band of stone divided the green fertile plains and forests from the desolate desert wastes of the other half. 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 wall expanded as he came nearer to the pygmy planet. 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. So slowly was the spinner dropping that the blackened desolation of the other hemisphere came sliding up beneath his boots. 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. Rolf's slitted gray eyes narrowed yet more and his hand dropped to the compact expoder machine-gun holstered at his hip. "Sorry," said the tall man as Rolf sprang easily from the ground to their side.
output:  It is abundant with water. It would be enough for all of Mars and the colonies.
options:  It is abundant with water. It would be enough for all of Mars and the colonies.  The presence of Altha, and her living here in secrecy.  It is a secluded area, not yet touched by most other people.  The miniature planet and the way it functions.