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A sudden spurt of blazing gas shot up from the center of the station. "Duck!" yelled Haines, and they fell flat on the ground. Burl held his hands protectively over his head, as an explosion shook the building.
There was no rain of rocks. Whatever the blast, Callisto's gravity was too weak to attract the debris that flew high above the station.
"It was an atomic explosion!" Haines shouted into his helmet mike. "They mined that station. Run for it!"
They raced for the rocket plane. As they ran, Burl felt the ground quiver beneath him, and huge cracks began to spread, rippling through the hard ground.
They reached the plane and piled in. Russ took off just as the surface cracked open in a thousand places like an ice sheet breaking in an Arctic thaw.
As they rocketed back to the Magellan, the whole polar cap, an area hundreds of miles around the Sun-tap station, split apart. Great spurts of liquid magma, the liquid gas-dust from the heart of the planet, shot up like fountains. Parts of the shell-like polar continent were disappearing beneath this new ocean.
"Their little atomic bomb shattered the thin crust. The whole polar island will probably sink," said Russ. "It was a clever trap. They knew what would happen."
"Saturn next," said Burl. "What'll they have set up there?"
They reached the Magellan, loaded the rocket plane aboard, and pulled out, setting their course for the ringed planet. But even as they did so, something was coming from Saturn to meet them.
CHAPTER FOURTEEN
Rockets Away!
THE NEXT lap of their journey was uneventful. Saturn, the next outward planet from the Sun, and the second largest, would present the same problem as Jupiter. This world, famous for its mysterious rings, was about 71,000 miles in diameter and had a large family of satellites nine in all. The Sun-tap station would be on one of these, Burl thought.
Saturn was also al