They spent an hour worming their way through the shambles that had been the well ordered interior of Spaceboat 6, before emerging to take stock of their loot on the ground outside. Both men knew that they were pitifully equipped to cover several hundred miles, on foot, in a completely hostile environment. Suddenly Madsen looked up from the sextant he was examining. "How come this gravity, Brain? I weigh about a hundred right now, I figure, and that's too much, by plenty. Japetus isn't a quarter the size of our moon." "It's supposed to have a core of heavy radioactive metals," said Morley, thoughtfully, "and a corresponding high density. Keeps it warm anyway, instead of a big icicle, like Phoebe." "Phoebe!" Madsen laughed. "I remember, back in '89--" He stopped abruptly at a rattling from the ledge. A green, little lizard-like creature was scrambling frantically over the granite, while hot in pursuit were three--spiders? Black, they were, a black like living velvet, and incredibly fast as they closed in, beady stalked eyes fastened on their prey. They were deliberately herding the desperate lizard toward a cleft in the rock. As the creature leaped into the opening, another spider dove at it from the recess. The others closed in. There was a hopeless hissing, a vicious clicking of mandibles. The struggle subsided. Once again the day was silent. Madsen holstered the blaster he had drawn and looked whitely at Morley. "Pleasant pets," he grunted. "Poisonous and carnivorous, too," said Morley, shakingly. "I remember reading that Valdez dissected one when he first landed here twenty years ago. One of his crew was bitten, and died in less than five minutes." Madsen was thoughtful. "We could stand a little briefing on the local flora and fauna, but palaver won't get us to the Equator. And that little stock treatise entitled 'Physical Attributes of Phoebe' is worse than useless. Lucky the sextant is O.K., we can at least check our latitude. There's just one flaw." "What's that?" "Which way do we go when we hit the line? The D.D.'s are spaced ninety degrees apart. We might be within a hundred miles of one. If we head the wrong way, we'd have three or four hundred miles to go. There's no method of figuring our longitude." Morley was staring sunward, with thoughtful eyes. "Yes, there is," he said quietly. Madsen's jaw dropped. "Give," he said. "We both forgot something we know perfectly well. Notice the sun? It hasn't moved perceptibly since we landed. Japetus doesn't revolve on its axis." "So what?" "Two things. One, no night, since we're on the sunward side. The sun will move from side to side in the sky, reaching its lateral limits when Japetus is in quadrature in regard to Saturn. If we were here for a month, we'd see Saturn rise, make a full arc through the sky, and set. Let's hope for a shorter stay." "Go on," said Madsen, and suddenly there was nothing patronizing or scornful in his voice.