Nebula (33 page)

“You mean that they don’t have sensors and defenses in that direction?” Seduro asked.

“No, they have defenses all around them, but this ship will signal that it’s another fighter that got repaired and is being piloted by robots and that it has new information and orders that they need. Igor will take care of all the communications and will look to them as a normal soldier robot in one of the alien fighters. Igor will tell them that high command wants them to get the new information and orders as quickly as possible, but that they don’t trust the communication network, so his instructions were to come in at high speed and deliver the message without risking any radio transmission of the new information. The alien force commander in the light cruiser must have orders to be careful for any deception since we’ve been counting on trickery to defeat them in each previous battle, but he would have to respond in a way that would let the fighter get close to his formation. So he’ll almost certainly instruct Igor to remain at a reasonable distance once he gets through the outer defenses, and he’ll probably send one of his fighters out to meet the new arrival and retrieve the new information and orders. That would be the cautious thing to do. It’s what I’d do if I were in that commander’s position. He’ll also probably deploy other fighters and defensive systems between Igor’s ship and his own formation.”

“So what good will this do?” Seduro asked, still agitated and not convinced that what Haverford was saying made any sense. But he was still willing to listen. Besides, neither he nor the others had any better ideas.

“If Milo just did as ordered, it would do little good, but he’ll continue at high light speed beyond the point where he was told to slow down, and he’ll launch one of the asteroid-buster torpedoes while he’s still going at 99.9% light speed. The asteroid-busters can’t achieve that speed on their own, but their engines are good enough to keep them from slowing down too much before they reach the alien ships, and the torpedo that he launches will be aimed at the command ship. If we can take it out, we can disrupt the entire alien operation. We think that they have one or two fighters that they were able to keep uncontaminated, and they probably have alien crews in them to back up the main command post in the cruiser, but if we take the cruiser out, it will definitely disrupt them for a few minutes, maybe even more.”

The tension in the room obviously decreased as everyone saw that there was a reasonably good chance that this might succeed. Billingsley seemed to relax to almost normal, and Seduro nodded his agreement that the plan made sense.

Haverford paused for a couple of seconds to give an opportunity for questions or comments. When there were none, he continued. “Once Milo launches that first torpedo, he’ll swing back out at high light speed, and if he can evade their fire, he can swing back in to try to take out the battleship with his second torpedo if our people on Mars haven’t already taken control of the big guns and done it themselves. If they already gained control and fired on the alien ships, he can just rejoin the rest of our force near Earth. Then, Brad’s team can destroy any alien ships in the area around Mars and between Mars and Earth, and our force can fly out to relieve them and establish permanent command of all the sensors and weapons that the aliens put there.”

“It sounds pretty risky,” Seduro said, turning toward Billingsley. “What do you think of it Abe?”

“It’s risky,” was the reply. “But what other options do we have?” He looked at Haverford, clearly addressing his question back to the commander of the space forces.

“The other options are worse,” Haverford replied. “The most that we’d do is delay things a bit, but in the end, the aliens would be able to attack Earth. I think that we can pull this off and bring the war either to a conclusion in our favor or into a stalemate where the aliens can’t reach Earth with any of their ships or long range weapons. A strong point on Mars, plus the mines and long range artillery that we can use in the region of space nearer to Earth, should prevent any direct assault on us. It’s pretty clear that we can’t defend Mars for more than one, or at most two, assaults, and once they get their base established there, we wouldn’t stand a chance unless the pathogens somehow infected the rest of their population. Brad’s plan to seize the alien base on Mars, and the diversion attack that Milo would launch, are our best bets.”

“What’s the probability of success?” Seduro asked.

“We’ve run some simulations and analytical models, and we estimate between sixty and seventy five percent, assuming that there are no major surprises.”

“I’d be a lot happier with ninety to ninety five. What if it fails?”

“We’d all be happier with a higher number,” Haverford replied. “The estimate was pretty much a worst case estimate. We used a high probability of failure for the synchronization of Milo’s attack with the actions of Brad’s troops, and we also made pessimistic estimates on the probabilities that some of Brad’s objectives won’t be met and that there would be more extensive combat on the surface. If things go better than these pessimistic estimates, the result would be a lot better, but we don’t want to make it sound too easy. In any case, all the other options have equally low probabilities of success, and even if they did succeed, they wouldn’t do anything but delay the inevitable assault on Earth.”

“OK,” Seduro finally said. “I agree. It’s probably our only shot at doing something decisive. Does anyone have any questions? If not, let’s get on with it.”

Brad arrived back on Mars thirty minutes after the end of the meeting at Ops. There was no time to waste, and he needed to make sure that everything was ready. He briefed the team on the plan that he and Haverford had developed and explained how they would synchronize their actions. This had all been worked out in detail with Haverford.

“We need to keep radio silence, so we’ll rely on what we can observe to tell us when we should start our end of the action. The first cue will be when the aliens complete installation of the equipment on Mars. They’ll certainly test all the weapons, so both we and Haverford will be able to see that. Milo will probably be ready at that point to start his move back toward Mars. Haverford estimates that it will take at least two or three days for the aliens to get everything up and running, and he’ll send Milo out on a course that takes him far above the plane of the solar system and then back down to a point about thirty light minutes from here, where he’ll wait until he sees the test shots. Then he’ll come back in at high speed. The detonation of his first torpedo is our cue to act. We all know what needs to be done, and we need to do it fast and without any errors. We’ll have a few minutes before the alien ships realize what’s going on, so we have to be able to take them out before they fire on us. Any questions?”

No one responded, so the briefing session ended and everyone got back to work on their own preparations.

*

Alien message traffic in the robot network and planning records stored in the archives told the precise date and time for the assault, and like clockwork, the ships appeared five hundred thousand kilometers above the surface of Mars and began to approach. It was an impressive fleet, with one battleship, two heavy cruisers, one light cruiser, twenty fighters, and fifteen robot ships. There were also a couple of large ships that looked like they might be transports, probably carrying the equipment and structural material to be brought to the surface and also probably acting as mother ships for assault craft. The aliens had obviously decided to risk almost all the remaining ships that were still serviceable, including a few that hadn’t been infected and could still be operated by alien crews and others that could be operated by soldier robots.

Harry and the others looked at the displays with views from several concealed telescopic video cameras and saw the massive assembly of warships that was now only about twenty thousand kilometers above the surface. They were hovering in gravity-stabilized positions, with one of the cruisers and a large transport ship directly over the alien base and with the center of the formation offset about fifteen or twenty degrees. No one said a word, and the only sound in the operations center was the heavy breathing of people who knew that they were on the verge of either succeeding in a complicated and vitally important task or facing a very swift death, leaving Earth exposed to an unstoppable alien assault. They knew that Haverford’s fleet would only be able to delay the inevitable by a few weeks or months if they failed. Harry had never felt this tense or this close to despair as now, and he expected that the others, even Lu’s team might feel the same at this point. The only release would come when they went into action, but that would probably be days, maybe a week or more, in the future, after the aliens had completed their installations and ran their tests. Until then, they would have to wait, and watch, and worry.

It wasn’t long, maybe only ten or fifteen minutes, before two assault craft emerged from one of the transport ships and descended onto the surface near the alien base. One carried a crew of six aliens and the other had six robots.

The aliens and robots disembarked and fanned out in what was obviously a preplanned reconnaissance of the area. Each alien was accompanied by a soldier robot. One pair went into the alien operations bunker and another went into the storage shelter. The other four did a thorough search of the area around the base, establishing a cleared circular area with a radius of about half a kilometer. It included the locations where Nebula’s facility and their external sensors and telescopes were buried under the Martian hillsides, and they passed by with no indication that they had detected anything. Lu was right about Ogre’s skill at cover and camouflage. So far, so good.

After completing a search of the area, the aliens sent a message that all was clear, and two more ships emerged from the large transport and descended. They were smaller than the assault ships and looked more like the types of shuttles that Nebula used. They flew to where the assault ships were sitting, and they settled down next to them.

Three aliens and three robots emerged from each of the shuttles. The robots looked more like Robby than Igor, so Harry assumed that they must be some sort of worker robots, probably built for specialized construction tasks. He connected himself to the robot network through his own worker robot and verified that this was indeed what they were. The six pairs of aliens and robots would be the construction workers. He told the others what he knew, confirming what they had already assumed.

The first thing that the six new alien-robot pairs did was to take some pieces of equipment from the shuttles. Then they deployed the equipment along the circular perimeter of the area that was reconnoitered earlier, at spacing of about fifty meters along the circle. When they completed this task, they all returned to the alien base. The aliens went inside to join the others. The robots remained outside and went into what appeared to be a sleep mode.

It was clear that the perimeter sensors and defenses had now been deployed, but Harry checked the data on the robot network to verify it. So now they were isolated inside the alien defensive area, as planned. The next step would be for the aliens to construct the long range guns and sensors around the planet. The team would wait and watch until it was time to act. Brad had told them that the waiting would be the hardest part, and he was right.

But the wait wasn’t very long. After several minutes, the aliens sent another message, and the transport ship descended. It was a large ship, larger than any that Harry had ever seen at the surface of a planet, and he was surprised that something that large could survive the pull of gravity without buckling or cracking. But he realized that the ability to control gravity would make this possible, only very complicated. It was beyond the capability that Nebula had, so there were some technologies that the aliens had that were beyond what Nebula’s scientists had seen. Hopefully, this wouldn’t be a factor in the operations yet to come.

A large port opened on the side of the transport. Several more worker robots emerged and were joined by the ones that had been standing idle. They began to remove pieces of equipment that were larger than the ones that had been in the shuttles. They sorted the pieces and arranged them in six groups, each one with an identical mix of parts. Then they loaded some of the parts from one group into the assault ships and the shuttles. This first load took only a fraction of the parts that had been placed in that first group. When the ships were loaded to capacity, they flew off. It was clear that the big guns were about to be erected, probably at six locations.

*

Three days passed, and they waited as the aliens went about their business. They seemed to be tireless, working around the clock and dragging equipment from the transport, loading it into the ships, and flying to the points where they wanted to place the sensors and guns. Some equipment was small and could be carried in the two shuttles. Others were larger and needed to be carried by the assault ships. Those large pieces were obviously parts of the plasma cannons, the ones that could reach a very long distance from Mars toward Earth. They could see why these huge weapons had to be located on a planet or a large pseudo-planet like the platform ship. No ordinary spacecraft, even an alien battleship, could carry those monsters.

Judith was particularly interested in these weapons. She studied imagery of the artillery pieces as they were unloaded from the transport ship and collected all the design data that Harry was able to extract from the alien archives. She busied herself with detailed measurements and with calculations on her computer and then announced that she thought she understood how the guns worked.

“These look like very impressive plasma cannons like we expected. But they’re a lot more than just bigger versions of the ones on the battleships. It looks like they consist of multiple launchers, probably about ten for each gun. The central structural element looks like it holds ten of them, and I assume that they’re all active launchers, not just aiming devices. That should give them rapid-fire capability equal to at least ten times our firing rate. I’m guessing that it may even be more than that. The structure of the launchers indicates that they may have multiple power feeds to let them come back on line quickly after a discharge, so we may be dealing with plasma cannons that are like the rotating cannons on combat aircraft. They might put out a nearly continuous stream of fire. Judging from the size and shape of the launchers, my rough estimate is that they might have a range that would be lethal out to fifty or sixty million kilometers against anything with shields less than one of our fighters. Even a fighter might be vulnerable at ranges over forty or fifty million kilometers. Those are very impressive guns. They have more than ten times the range of our big guns, and they wouldn’t be limited by long recharge time between shots. We definitely need to get control of them. If we don’t, Haverford won’t have a chance against them.”

“Do you think that we’ll be able to control them without any time to practice?” Brad asked.

“I think so. The fire control unit looks pretty much the same as the ones for the other plasma guns, and we already know how to use them. It just has a larger view screen and an extra lever that seems to have several discrete positions. I’m guessing that the lever controls the speed of fire, probably up for faster and down for slower. That seems to be the standard way that they do things. There’s a position at the bottom that lets it move a bit sideways, probably to lock it into a single fire mode instead of the rapid fire ones. Other than that, it looks the same as the others. This button here is almost certainly the fire button,” and she pointed to the picture on the screen.

“If it’s set for rapid fire, how do you turn it off once it starts?” Lu asked.

“Good question,” Judith replied. “I’m guessing that they push the button once to start firing and again to stop since there are no other controls that I can see. It’s not like a trigger that you hold until you want to stop shooting. That’s my guess, but Ludmila is trying to figure out how the programming differs from the simpler fire control units that we already have. That’s important if we have to operate the guns using our remote control unit. It’s built to operate the standard guns that we captured, so some new software will be needed if we want to get into the more advanced functions in these fire control units.”

“So that thing will be like a buzz saw once you push the button?” Lu asked.

“If it’s in the automatic fire mode, I guess that’s what would happen. If we’re operating it from the remote control, I’m not sure yet how we could stop it from firing, but there must be a way since the remote control gets into all the internal functions. Ludmila and I are working on it, and Ludmila’s confident that there’s a way to turn it on and off and also to adjust the firing modes. She has the code that Harry got from the archives, and she’ll figure it out.”

“Well, we’ll get a chance to find out a lot when they test the things,” Yuri commented. “I expect that they’ll check all the modes in all the guns. They’ll probably put the operating stations outside their bunker, like they did for the other plasma cannon. We’ll be able to look through our telescopic cameras and see what they do, so we’ll be able to operate manually once we seize control.”

“Are the aliens able to control all the guns from one station?” Brad asked.

“No,” Judith replied. “It looks like each gun will have its own control station. They’re already setting up the third one outside the base.”

“Can you connect to all of them with the remote box?”

“One remote control box will be able to connect to one of their fire control units. We can select the frequency and codes for any of them, but only one at a time.”

“Then we’re limited to only one of the guns until we can take control of the alien equipment?”

“We should be able to control at least four of them remotely if we have to. We started modifying three other computers and radios to convert them into remote control units. That should be complete in a few hours once I can get back to work. Doug and Nigel are helping me, and it’s going well. We’ll pick the four guns that give us the best coverage of the region where the alien ships are. One of them will probably be at this location. We already see them setting it up. We’ll have to wait until they deploy the guns to decide which other ones to use.”

“OK,” Brad replied. “The most important things to do as soon as we see Milo attack are to take out any aliens that are at the base, disable all their robots on the surface, and destroy the alien ships. We’ll need to get the big guns firing at the ships as soon as possible, so we’ll have to rely on those four remotes until we can get into the alien base. The alien ships will start firing on everything around here once they figure out what’s happening, and we can’t count on Haverford’s plan to delay them by more than a few minutes. I want Harry and Yuri to concentrate on the robots. Judith, Ludmila, Doug, and Nigel will be on the four guns, and Mikio will work the tactical radio net. Lu will handle the operation outside against the aliens. Is that clear? Does everyone know what they’re supposed to do?”