"Let's climb a ways, and if we don't find anything there, go back to the ship and try somewhere else."
"I'll buy a chunk of that."
They started up the hill before them. The climbing was difficult because of the ice and because in most places the side of the hill was not a gradual slope, but a starkly steep climb. It was evident there had been no gradual "weathering" here, to produce rounded edges and rolling slopes, although there were occasional smooth places. These, though, the boys knew could not be climbed at all without special equipment which they did not carry.
"This isn't frozen-water ice, is it?" Jon asked as they panted upward.
"No, silly. There can be no water vapor here, any more than there is on Neptune or Pluto back home. This is mostly frozen carbon dioxide."
"Well, it's just as cold and just as hard to climb as polar ice."
They climbed the quarter mile to the crest of the first hill and peered eagerly over its top. In front and slightly below was another valley—not as deep as the one in which their ship lay, but even larger. From their higher position the floor of this new valley seemed quite smooth.
"But that can be just an optical illusion," Jak answered Jon's statement, adding, "the glare of white would make it look smoother from a height."
Jon ignored the tone of superiority. "Good thing our suits have tinted lenses. Do we go down?"
"Natch." Jak had already started. "Off there to the right and part way down are some darker places. I want to look at them."