Tom turned back to the intercom.
"Power deck, execute!"
At more than five thousand miles an hour, the _Polaris_ hurtled toward its destination. One by one the remaining ships moved alongside until all six had their needlelike noses pointed toward the pale satellite of the Moon.
"I'd like to know what your plans are, Tom," said Strong, when the long haul toward the Moon had settled down to a routine. "Just idle curiosity, nothing more. You don't have to tell me if you don't want to."
"Golly, yes," said Tom, "I'd be very grateful for your opinion."
"Well, let's have it," said the captain. "But as for my opinion--I'll listen, but I won't say anything."
Tom grinned sheepishly.
"Well," he began, "if I were in command of the invading fleet, I would strike in force--I'd have to, to do damage with only eight ships. There are three possible approaches to Luna City. One is from the Earth side, using the eclipse corridor of darkness as protection. To meet that, I've stationed two ships at different levels and distances in that corridor so that it would be impossible for an invasion to pass unnoticed."
"You mean, you'd be willing to give up two ships to the invader to have him betray his position. Is that right?"
"Yes, sir. But I've also sent Squadrons B and C to sectors eight and nine on chart seven. So I have a roving squadron to go to their aid, should the invader strike there. And on the other hand, should he manage to get through my outer defense, I have Squadrons D and E over Luna City itself as an inner defense. As for Squadron A, we'll try to engage the enemy first and maybe weaken him; at least reduce the full force of his attack. And then have Squadrons B, C, D and E finish him off, by attack from three different points."
Strong nodded silently. The young cadet was shaping up a defensive strategy with great skill. If he could only follow through on his plans, the invaders of Luna City wouldn't have much chance of success--even if willing to take heavy losses.
Roger's voice came on. "Got a report for you, Tom. From command ship, Squadron B. They've sighted the invaders and are advancing to meet them."
Tom checked his charts and turned to the intercom.
"Send them this message, Roger," he said. "From Starlight, to command ship, Squadrons B and C--approach enemy ships from position of chart nineteen, sections one through ten."
"Right!" said Roger.
Strong smiled. Tom was driving his heaviest force between the invading fleet and its objective--forcing the aggressors into a trap.
Tom gave more crisp orders to his squadrons. He asked Roger for an estimated range, and then, rechecking his position, turned again to the intercom.
"Astro, how much could you get out of this baby by opening the by-pass between the cooling pumps and the reactant chamber? That'd mean feeding the stuff into the motors only half cooled."
Strong turned, started to speak, then clamped his lips together.
"Another quarter space speed, roughly," replied Astro, "about fifteen hundred miles more an hour. Do you want me to do that?"
"No, not now," replied Tom. "Just wanted to know what I could depend on, if I get stuck."
"O.K.," said Astro. "Let me know!"
"Why use emergency speed, Corbett?" asked Strong. "You seem to have your enemy right where you want him now."
"Yes, sir," replied Tom. "And the enemy knows I have him. He can't possibly attack Luna City now. But he can still run away. He can make his escape by this one route."
Tom walked to the chart and ran his finger on a line away from the invader's position into the asteroid belt.
"I don't want him to get away," Tom explained. "And with the extra speed, we can cut him off, force him to turn into a position where the remainder of my fleet would finish him off."
"You'll do this with just the _Polaris_?"
"Oh, no, sir," said Tom. "I'd use the _Arcturus_, _Capella_ and the _Centauri_, as well."
"Are you sure those other ships can equal your speed?"
"They've got exactly the same type engines as we have here on the _Polaris_, sir. I'm sure they could--and with perfect safety."
Strong hesitated a moment, started to ask a question, then stopped and walked to the chart screen. He checked the figures. He checked them four times, then turned to Tom with a grin and an outstretched hand.
"I've got to offer my congratulations, Tom. This maneuver would wipe them out. And I've got a notion that you'd come off without the loss of a single ship, plus, and it is a big plus, keeping the invaders more than fifty thousand miles away from their objective!"
The captain turned to the teleceiver. "Rocket cruiser _Polaris_ to control tower at Space Academy--"
There was a crackle of static and then the deep voice of Commander Walters boomed from the speaker.
"Spaceport control to _Polaris_. Come in, Steve."
In a few brief sentences, Strong outlined Tom's plan of action to the Academy commander. The commander's face on the teleceiver widened into a grin, then broke out in a hearty laugh.
"What's that, sir?" asked Captain Strong.
"Very simple, Steve. All of us--all the Academy top brass--develop a foolproof test for cadet maneuvers. And then your young Corbett makes us look like amateurs."
"But didn't you expect one side or the other to win?" asked Strong.
"Of course, but not like this. We've been expecting a couple of days of maneuver, with both sides making plenty of mistakes that we could call them on. But here Corbett wraps the whole thing up before we can get our pencils sharpened."
"Better stuff cotton in Corbett's ears before he hears all this," rasped Roger Manning over the intercom. "Or his head'll be too big to go through the hatch."
"Quiet, Manning," came Astro's voice from the power deck. "Your mouth alone is bigger than Tom's head'll ever be."
"Look, you Venusian ape--" began Roger, but Commander Walters' voice boomed out again. His face on the teleceiver screen was serious now.
"Attention! Attention all units! The battle has been fought and won on the chart screen of the rocket cruiser _Polaris_. The Luna City attack has been repelled and the invading fleet wiped out. All units and ships will return to Space Academy at once. Congratulations to all and end transmission."
The commander's face faded from the screen. Captain Strong turned to Tom.
"Good work," he said.
He was interrupted by a crackle of static from the teleceiver. A face suddenly appeared on the screen--a man's face, frightened and tense.
"S O S." The voice rang out through the control deck.
"This is an S O S. Space passenger ship _Lady Venus_ requests assistance immediately. Position is sector two, chart one hundred three. Emergency.
We must have--"
The screen went blank, the voice stopped as though cut off by a knife.
Strong frantically worked the teleceiver dials to re-establish contact.