In the thirty years since the exploration of Jupiter's satellites had begun, Callisto had had a very different history from the rest. On Ganymede, a hundred or so engineers had been working all that time on the tremendous task of raising the satellite's mean temperature to the point where an atmosphere could be provided and open-air cities and farms built in which Earthmen could live. The smaller satellites had been largely ignored. But it had been found that Callisto had large deposits of ore of such quality that, in spite of the tremendously long haul required to carry anything from there to the inner planets, it was worth while beginning mining operations. Up went the insulated, airtight domes, out came the colonists, down went the mine shafts.
It was a hard life. Crystalline rock was cut by machines at the mine-faces, and by the time other machines had brought it up the shafts to the surface-level in the domes, it had become amorphous and powdery, its crystalline structure destroyed by being heated to twenty degrees below zero Centigrade. When you repaired machinery below the surface, you wore sixty kilograms of spacesuit (Earth weight), and a failure of any item of equipment or a fumble by any member of your crew might mean sudden death. The walls of the dome shut you in from the sky, for the vacuum out there was death too; when you did get up to the observatory to see the sky, you saw Jupiter, weirdly streaked with brilliant color—if your dome was on the side of Callisto toward Jupiter. Otherwise, you looked across twenty million kilometers of vacuum to the nearest star.
It was a hard life, and no life for a lone wolf. There were no homestead farms to be settled by lonely pioneer families. Callisto was a sterile place, and to keep life going there at all men had to work together. Cooperation was a lesson Earth civilization had learned only after thousands of years of oppression and war; a lesson that had to be learned before men could cross space; and a lesson that was very difficult to forget on Callisto. At least for most people.
Rita and Cliff Belden had control of the trade between Callisto and the inner planets. It didn't start as control, though; the way it began was this: Once the colony had been well established, its operation was left completely up to the Callistans, who shipped as much of their goods to Earth as they could manage, and requisitioned as much food and supplies from Earth as they needed—which was really the best way. The inner planets could not very well take part in the planning of Callisto's activities, since there was no radio contact and the trip took over two months by freighter even when the relative positions of the planets in their orbits was most favorable. One freighter shuttled back and forth between No. 2 Dome on Callisto at one end and any of several inner-planet ports at the other. Rita and Cliff Belden were the two Callistans whose job it was to run that freighter.
The little colony was absolutely dependent on the supplies they brought. This fact was obvious to everybody, but the Beldens made a deduction from it which was unprecedented on Callisto: they could threaten to withhold the supplies and thereby force the rest of the colonists to agree to whatever they asked—provided they could make the threat stick. They made the attempt. On one of their trips back from Earth, they put the ship into an orbit around Callisto instead of landing, and announced they would not land until their henchmen on Callisto were in control.
And the henchmen did a thorough job of taking control. All the details were taken care of: They quickly seized the radio transmitters that maintained contact with Ganymede, they confiscated all the reserves of spaceship fuel they could find, they clamped down as tightly as they could on communication between the domes; then they started keeping a close check on every tool that could be used as a weapon. There was just one place they slipped up. Their search for fuel wasn't good enough.
The people of No. 4 Dome pooled the fuel they had hidden from the Beldens; they seized from the Beldens' guards the Dome's tiny spaceship, which had been assembled on Callisto and which had never been intended to leave the Jupiter system; and they sent the ship off for Venus, with Garcia and Birkerod aboard. Venus was the only possible destination, with the planets' positions in their orbits as they were then: to reach Earth or Mars would have taken either more fuel than they had, or much more time than they could spare.
As it was, the trip took eight months.
On Venus there was no hitch. Garcia and Birkerod went to the Liaison Office in Kreingrad, as planned, and were provided with the Tang Chuh-Chih, with a load of supplies—and with Nick Pappas, a former Callistan who wanted to return there. They followed the Liaison Office's suggestion and took Pappas aboard.