O'Day was in the pilot's seat, his fingers poised and ready above the innumerable banked studs. Of him Flick asked, "What's up, Lark? You're as fidgety as a yogi on a cactus mattress."
O'Day dismissed the query with a swift, impatient shake of the head. "Not now, Flick, if you don't mind. I'm busy."
Muldoon transferred his questioning to Warren.
"Busy? What's all the fuss about? All we've got to do is slide into Mars and make a landing, isn't it?"
But Warren, too, showed no inclination to talk. He said to the man at the controls, "Co-ordinates look good, O'Day. Both moons are on this side. Of course, that may or may not mean anything. You never can tell."
"What is this?" demanded the now completely baffled Muldoon of the only remaining space officer. "You guys act like you're expecting trouble. What's the matter? Do you think the Martians are hostile?"
Lieutenant MacDonald smiled thinly. "It's not the Martians we're worried about, Flick. It's those damned moons."
"What about them?"
"Well, we want to make sure we clear them, that's all. You see, Mars has two moons, Deimos and Phobos. They're tricky little gadgets to calculate when you're plotting a landing on the mother planet. Both of them travel like bats out of hell. The inner one, Phobos, takes only seven hours and thirty-nine minutes to make a complete revolution. Deimos scoots along even faster. Though it's three times as far from its primary as Phobos, it gallops through its orbit in thirty hours and twenty minutes."
"So," Muldoon said, "What? You're not afraid of one of them hitting us, are you? We're traveling faster than they are. And if you know where they're going to be at any given moment—"