"Why on earth would he want dragons clinging to that bloody framework, thousands of miles above Pern?" F'lar demanded.
"To accustom dragons to being in space," Jaxom replied.
"That's not all," Robinton said in a slow, thoughtful tone.
"No." D'ram sat erect and alert. "The dragons must move the Yokohama."
"Why?" Lessa asked. "What good would that do?"
"To ram it at the Red Star," D'ram said.
Jaxom, Piemur, and F'lar shook their heads.
"Why not?" Lessa demanded. "That must be why he wanted the fuel in the tanks."
Jaxom smiled wryly at her ignorance. "That drop of fuel would not explode on impact, and ramming the Red Star with the Yokohama, ponderous as it is, would not alter its orbit one bit. But I grant you, he needs the dragons to move something."
"Let's ask him!" Robinton suggested, standing and starting for the door. When the others did not move, he turned back at them. "Well, don't we want to know?"
"I'm not so sure I do," Lessa murmured, but she rose and followed the others as they trooped down the hallway to Aivas's room.
Jaxom, Jancis, and Piemur closed the doors into the various rooms occupied by students and, when all were inside Aivas's chamber, that door was closed. Piemur leaned back against it.
"What do the dragons have to move and where?" F'lar asked with no preamble.
"So you have perceived part of the plan, Weyrleader."
"You mean to use the Yokohama to ram the planet?" Lessa asked, still sure that she had the answer.
"That would be totally ineffectual, and the Yokohama is needed as a vantage point."
"Then what?" F'lar insisted.
A picture came up of the Red Star, with details gleaned from Wansor's patient study of the face the planet presented its viewers. A deep chasm could be seen running diagonally across one hemisphere-an unusual feature caused, Aivas had said, by an earthquake of incredible force.
"You all see this fracture. It is entirely possible that the chasm goes deep into the planet. It is probable that an explosion of sufficient magnitude at this point would have the desired effect of altering the planet's orbit. Especially when the planet is already perturbed by its proximity to the fifth satellite of this system." The visual altered to the familiar diagram of the Rukbat system. "Ordinarily an explosion of this magnitude would be impossible to effect. Not only because of the difficulty of amassing the elements required to make such a blast, but because it is nearly impossible to prevent chaotic elements from entering the equations of motion of the Red Star and even of the other planets.
"It is apparent from Master Wansor's investigations that the fifth planet is devoid of atmosphere and life. It is also at its farthest distance from Pern. There will be some perturbations throughout the system, but these have been calculated as negligible in the face of the desired result, the relief from any further incursions of Thread on this planet."
For a very long moment, no one spoke.
"We have no such exploding capability," Jaxom said.
"You do not. The Yokohama, the Bahrain, and the Buenos Aires do."
"What?" F'lar demanded angrily.
"The engines," Jaxom said. "The bloody engines. Oh, you are devious, Aivas!"
"But the engines are dead!" "There's not enough fuel!" "How would we get them there?" Everyone tried to be heard.
"The engines are dormant," Aivas said over the uproar. "But it is the material in the engines that will provide the explosive power. If antimatter is allowed to contact matter without controls, the result will suit your needs."
"Now wait a moment-" Jaxom called for order over the babel of questions. "You specifically stated in those engineering lectures to Fandarel that the antimatter is held out of contact with matter in the densest metals Mankind has ever forged. We don't have the equipment to penetrate those casings. Or is Fandarel working on something we don't know about'?"
There was a little pause, and Jaxom found himself agreeing with master Robinton that Aivas seemed to laugh to himself sometimes.
"It is true that the safety factors built into the great interstellar engines were immensely sophisticated, and that schematics for their design are not available in the engineering data," Aivas said at last. "But it has long been the case that complex things can be attacked best by simple methods. This facility must also obey the stipulation that you are not to be instructed in levels of technology beyond that of your ancestors. Fortunately you already have an agent that will provide the penetration. You have used it in every Fall for many centuries."
"HN03!" Piemur said in a gasp.
"Correct. The metal casings of the matter/antimatter drives are not impervious to its erosive effect." The visual of the Yokohama's engine shaft reappeared, but now there were large extraneous tanks placed on the drive cube. "It will take time, which is why there is a wide window of two weeks for this part of the activity, but the acid will penetrate the casings, and once the magnetic chamber is broached, matter and antimatter will self-destruct, causing the cataclysmic explosion necessary to shift the Red Star's orbit. Any further questions?"
Jaxom broke the silence that time. "So all the Weyrs of Pern will be needed to take the engines, not the ships, between to the Red Star. To drop them into the chasm?"
"To drop them might displace the HN03 tanks."
"How heavy are those engines?" F'lar asked.
"Their mass is the one weak point of the plan. However, you have constantly stated that the dragons can carry that which they think they can carry."
"Correct, but no one has ever asked them to carry engines!" F'lar replied, awed by the scale of the loads.
Jaxom began to chuckle and received offended stares. "That's why the bronzes have been exercising in free-fall-to get them used to things being so much lighter in space. Right, Aivas?"
"That is correct."
"So if we don't tell them how much those bloody things weigh..."
"Now, really, Jaxom," F'lar began.
"No, really, F'lar," Jaxom replied. "Aivas is applying a valid psychological tactic. I think it'll work. Especially if we think it can work. Right?" He gave F'lar a challenging look.
"Jaxom makes a good point," Lytol said. Beside him, D'ram nodded accord. "With many dragons, all working together... it could be done. No one dragon bearing more than his fair share of the burden, everyone believing that he can succeed. That framework is convenient. Each dragon will be able to grip the load."
"With padding on their feet to reduce the effects of spacecold metal," Aivas added.
"And take that much weight between?" Lessa asked, still skeptical.
"You know," F'lar said, rubbing his jaw speculatively. "I think they could do it-if we think they can. Tell me how Ruth reacted to being in space, Jaxom."
"Wait a minute," Lessa said, holding up her hand, her brow wrinkled in concentration. "How long would such a maneuver take? We could get an engine between, but to go that distance between..."
"You and your queen Ramoth traveled backward in time..."
"And nearly died," F'lar said, his tone as bitter as the look he gave his weyrmate for the anguish he had suffered then.
"The riders will all have oxygen-which is doubtless what you lacked, Weyrwoman-to breathe, and protective suits."
"There aren't that many!" D'ram protested.
"Not yet," Piemur said, his eyes glinting, "but Hamian's turning out the plastic-coated fabric faster than Master Nicat's men can glue the pieces together."
"From what has been said by every rider interviewed, only eight seconds elapse to reach most destinations here on Pern," Aivas went on. "Of those eight seconds, the dragons seem to use a basic five or so to assimilate their coordinates, and the rest of the time for the actual transfer. Using this premise and adapting it to a logarithmic computation, assume that travel takes I second for 1,600 kilometers, 2 seconds for 10,000, 3.6 seconds for 100,000, and 4.8 for I million and 7 to 10 seconds for 10 million. While this method of transference is still incomprehensible to this facility, it does appear to work. Therefore, knowing the approximate distance from Pern to the Red Star, it is easy to compute an interplanetary jump. It has also been established that dragons are able to function for fifteen minutes before their systems are in oxygen debt-more than enough time to make the journey, position the engines in the chasm, and return. The dragons are accurate fliers."