know. I've seen the evidence here. Sabotage and murder." She pressed the button and waited wearily for a reply. "Ser Turco," Kollert said, "you have ten hours to make an effective course correction. We estimate you have enough reaction mass left to extend your orbit and miss the Earth by about four thousand kilometers. There is nothing we can do here but try to convince you" She stopped listening, trying to figure out what was happening behind the scenes. Earth wouldn't take such a threat without exploring a large number of alternatives. Kollert's voice droned on as she tired to think of the most likely action, and the most effective. She picked up her helmet and placed a short message, paying no attention to the transmission from Earth. "I'm going outside for a few minutes." The acceleration had been steady for two hours, but now the weightlessness was just as oppressive. The large cargo handler was fully loaded with extra fuel and a bulk William Porter was reluctant to think about. With the ship turned around for course correction, he could see the Moon glowing with Earthshine, and a bright crescent so thin it was almost a hair. He had about half an hour to relax before the real work began, and he was using it to read an excerpt from a novel by Anthony Burgess. He'd been a heavy reader all his memorable life, and now he allowed himself a possible last taste of pleasure. Like most inhabitants of the Moon, Porter was a Geshel, with a physicist father and a geneticist mother. He'd chosen a career as a pilot rather than a researcher out of romantic predilections established long before he was ten years old. There was something immediately effective and satisfying about piloting, and he'd turned out to be well suited to the work. He'd never expected to take on a mission like this. But then, he'd never paid much attention to politics, either. Even if he had, the disputes between Geshels and Naderites would have been hard to spotthey'd been settled, most experts believed, fifty years before, with the Naderites emerging as a ruling class. Outside of grumbling at restrictions, few Geshels complained. Responsibility had been lifted from their shoulders. Most of the population of both Earth and Moon was now involved in technical and scientific work, yet the mistakes they made would be blamed on Naderite policiesand the disasters would likewise be absorbed by the leadership. It wasn't a hard situation to get used to. William Porter wasn't so sure, now, that it was the ideal. He had two options to save Earth, and one of them meant he would die. He'd listened to the Psyche-Earth transmissions during acceleration, trying to make sense out of Turco's position, to form an opinion of her character and sanity, but he was more confused than ever. If she was rightand not a raving lunatic, which didn't seem to fit the factsthen the Hexamon Nexus had a lot of (17 of 197) explaining to do and probably wouldn't do it under the gun. The size of Turco's gun was far too imposing to be rationalthe destruction of the human race, the wiping of a planet's surface. He played back the computer diagram of what would happen if Psyche hit the Earth. At the angle it would strike, it would speed the rotation of the Earth's crust and mantle by an appreciable fraction. The asteroid would cut a gouge from Maine to England, several thousand kilometers long and at least a hundred kilometers deep. The impact would vault hundreds of millions of tons of surface material into space, and that would partially counteract the speedup of rotation. The effect would be a monumental jerk, with the energy finally being released as heat. The continents would fracture in several directions, forming new faults, even new plate orientations, which would generate earthquakes on a scale never before seen. The impact basin would be a hell of molten crust and mantle, with water on the perimeter bursting violently into steam, altering weather patterns around the world. It would take decades