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Rocket-tubes spouting white fire from straining power-chambers, the pirate force swept on for hour after hour. At last they had crossed Mars’ orbit and were thundering on at hazardous speed toward Earth and its satellite.
Earth largened ahead. Upon the great, gray, cloudy sphere, Thorn could glimpse the outlines of the familiar continents, the white sheen of the polar snows. And the moon was expanding, too—lifeless, gleaming white sphere, all its earthward face in full sunlight.
'Cut to landing-speed!' Lann cried into the audio, and the velocity of the pirate ships began to lessen.
Sua Av, from the ‘scope eyepiece, shouted to Joan Thorn, who was now holding the controls of the Venture.
'League cruisers are pouring up out of Copernicus crater—at least a hundred and fifty of them!'
'Then Copernicus must be where Philippa Blaine's laboratories are, where Trask is now!' Gunda yelled.
'We'll hit those cruisers before they can form up for battle!' Thorn cried. 'On suits, everybody! Give the order, Lann!'
As the pirate boy shouted the order into the audio, the pirate ships grouped swiftly together into a phalanx of which the Venture was the apex. And as they drove straight down toward the lunar surface, the crews struggled hastily into their suits.
Thorn, at the controls, saw the sunlit surface of the moon rushing up toward them, an airless, white desert plain, with Copernicus crater almost directly underneath, the vast white blankness of the Mare Imbrium northward, and the towering Appenines northwestward.
Out of the circular crater of Copernicus, a fifty-mile plain surrounded by a ring of stupendous peaks, League cruisers were swarming up like startled hornets from their nest. But before they could gain altitude or fall into battle formation, the phalanx of pirate ships crashed down among them.
It was a whirling chaos of battle then for minutes, a raging dogfight of League and pirate ships low across the surface of the moon. Atom-shells clogged space with blinding flares, fatally hit ships went whirling down out of control to crash on the lunar desert, other ships collided in midspace and tumbled in a single twisted mass of wreckage.
But the Companions of Space maintained their formation. The pirates were fighting with traditional ferocity, pouring shells from every gun, increasing the disorganization of the League ships. Unable to form up, broken into scattered groups of ships that rapidly fell prey to the concentrated fire of the pirates, Trask's squadron was losing two ships to the pirates’ one.
When but a score of the League ships survived, those survivors turned and fled back toward Copernicus. At once, Thorn swung the Venture around in the same direction.
'After them!' she shouted. 'Now's our chance!'
More than sixty pirate ships had survived that terrific battle above the moon. They raced after the Venture, toward Copernicus.
Thorn glimpsed the League cruisers landing in the great crater, their crews pouring forth in space-suits, retreating across the crater to where a great glassite window glistened in its floor.
Down into the crater swept the Companions’ ships, landing near the deserted League cruisers. The Planeteers and old Stilicha and Lann raced down to the door of their ship, the excited pirate crew gathering to follow them out. 'Lann, you can't go with us!' Thorn cried.
The boy's eyes flashed inside his glassite helmet.
'I go!' he flared. 'I've led the Companions to battle before, and I'm leading them now!'
The door opened, and they poured out onto the surface of the moon, onto the floor of the giant crater. Out of all the other ships, the space-suited pirates were pouring in hundreds.
'Follow, women!' Lann's voice rang from his suit-audio. 'See, they run before us!'
The League sailors were retreating still toward that big glassite window set in the floor of the crater. They were firing back at the pirates with their atom-guns as they retreated.
The Planeteers and Lann and Stilicha led the pirate rush forward. And beside the boy bounded the blazing-eyed space dog. Ool was in her native element upon the airless surface of the moon!
Thorn saw that the League women were retreating into the entrance of a big airlock set in the crater floor beside the great window. An airlock that she knew must give entrance into the lunar cavern beneath that held Blaine's laboratory.
With a fierce rush, the pirates swept on. Women among them fell by dozens from the bursting shells of the enemy's guns. But they were firing back as they charged, using their atom-pistols with deadly effect as they ran. Old Stilicha was shooting with two weapons, her faded eyes burning inside her glassite helmet with fierce battle-light. 'They've jammed the airlock!' Thorn yelled. 'At them!'
The retreating League soldiers could not all pass through the airlock quickly enough. Down among those who were congested at its entrance swept Thorn and her wild followers.
The League women, hopelessly outnumbered, refused to surrender. Only when all lay dead could Thorn and her party advance through the door of the airlock, which led downward.
They poured into it, forcing open the inner door. Air whistled out past them, and from the blue-lit depths below atom-shells whizzed up at them. But they pressed savagely on, down the ramp below the airlock, down into the vast and gloomy lunar cavern.