Nebula

by Howard Marsh

  He looked straight at Gladys, who was sitting at the table with her arm bandaged all the way from her wrist to her neck. “So, what’s going on with these bugs? You said they would kill most of those alien bastards?”

  “They’ll do the job,” Gladys replied. “It’s just going to take a bit longer. I talked with Nigel and Mikio about it, and they told me that the pathogens will work, but it won’t be as quick as they thought.”

  “How much longer? We can’t hold them off forever. What went wrong?”

  “Well, we’re not exactly sure. We ran into something that we never expected. When we did medical tests on the aliens that were captured and brought here, we thought that they were already sick. Their body temperatures were about three degrees Celsius above ours, so we thought that they had high fevers. But it turns out that’s normal for them. The high body temperature was something that Nigel and Mikio didn’t figure into their estimates. They looked at the virus growth at body temperatures like our own. They also had to do the development and testing with alien tissue that wasn’t in the normal, living condition, with all their antibodies and other defenses. The viruses don’t work the same way in living aliens, but they’ll still infect them and kill most of them. It’s just going to take a bit longer to incubate and spread. That’s all. It’s still going to work.”

  “Are you testing the pathogens on the captured aliens?” Billingsley asked.

  “No,” Gladys answered. “There’s no point in it. By the time we notice anything, they would already have worked at the alien fleet, and we might have better use for those aliens later. Besides, my staff and I wouldn’t want to do something like that on a prisoner, even one of these aliens.”

  Billingsley stopped pacing for a moment and looked at her. “OK. Well, your viruses better start working soon. Brendan, how much longer can we hold them back?”

  Haverford was prepared for that question. It was on all their minds. “We should be able to hold them back for at least another few days. We have all their plans from the intercepted messages, so we know exactly what they’ll do, and we’re already prepared to block their first attack, the one with the robot ships, and then disrupt their second phase. That should stop them for one day, and they’ll have to coordinate with their high command at the fleet to change plans. The travel time for those messages back and forth should take another two days, so we’re good for at least three days. After that, we expect them to move toward Mars so they can set up a base to build that platform ship and whatever other things they need for an advance toward Earth. They’ll still be worried that we may have strong defenses here, so they’ll be pretty cautious, especially after they see how we destroyed all those robot ships in their first attack. It should look to them as if we hit them with long range artillery from Earth, not from mines that were placed exactly where they would be when they slowed down from high relativistic speed.”

  “So you figure that we can hold for another three or four days?” Billingsley asked.

  “At least that long. We can defend the approach to Mars and probably delay them for at least another day or two. Then, we can try to disrupt them when they do land on Mars, but that will be a difficult covert op that might work once or twice and maybe give us another day, not much longer. I’m sending my best team to reinforce Brad’s people, and they’ll do whatever they can.”

  Billingsley thought for a few seconds and did the math in his head. “So, if this plague doesn’t break out in the next five or six days, we have a big problem?”

  “That will definitely complicate things,” Haverford said. “But we wouldn’t just collapse even if they do get themselves set up on Mars. It’s still going to take them time to build what they need and to move in stages toward Earth. Don’t forget that they still think that we may have strong local defenses, so they’ll move cautiously, keeping their long range artillery safe from any counterattack while they bring it close enough to hit Earth. If our bugs start to work before they get here, we may still be OK.”

  Brad had been sitting quietly as the exchange went on, and now he spoke up. “Another thing to remember is that it would take a day for us to know that something was happening at the fleet. The disease may already be breaking out. Messages about it just haven’t reached us yet.”

  “OK, let’s get on with the planning,” Billingsley said as he returned to his seat at the table. “Brendan, let’s hear where we stand.”

  “First off, our preparations went faster than we expected,” Haverford replied. “We managed to outfit a few of our large transports with the cannons from the battleship, and Ludmila was able to put her software into five of the soldier robots. So we have three transports with the big plasma cannons and the alien fighter with the EMP cannon for long range artillery to use with our fighters. The five new soldier robots can be added to the worker robot with our team on Mars. It would look to the aliens like the robots were just waiting there for them. They’d never suspect that we took control until we start to use them.”

  Haverford then paused and went to the display control computer. “Here’s our plan,” he said. The large screen display showed the plan consisting of five phases. Haverford explained that the first two phases were based entirely on what they knew of the aliens’ plans to probe Earth’s defenses and to tailor their actions based on what they saw.

  “Everything is intended to reinforce their impression that we’re a lot stronger than we really are. The first phase is our reaction to their robot ships that will come at us from a high angle above the Earth’s orbital plane. They’ll come in at near light speed and then rapidly decelerate here.” He pointed to a three-dimensional perspective map. “This is where we deployed a pretty dense minefield. It should take most of those ships out, and it would look to the aliens observing from out beyond Jupiter as if we hit them with Earth based heavy artillery. They don’t know that we prepared the minefield to correspond with their planned attack route, so they’d have to assume that we either have very good artillery or have mined our local area so densely that we could have had this type of coverage over the full sphere of possible attack routes.”

  “What about any leakers that the mines don’t get?” Billingsley asked.

  “I’ll have fifty fighters stationed just inside the minefield. That will be more than sufficient.”

  The display then changed to show the second and third echelons of the alien battle group, and Haverford continued with a description of phase two of Nebula’s plan.

  “We know that this two-echelon formation is a maneuver group intended to engage our fighters unless we retreat back to Earth after destroying their robot ships. If we come out to meet them, the forward echelon will engage us in direct combat while the rear echelon will provide heavy artillery support. They mainly want to get a good comparison of our long range weapons with theirs. If we retreat, they’ll think that we’re trying to lure them into range of our heavy artillery based on Earth or maybe on the Moon. Remember, they still think that we have those kinds of weapons, so they won’t take the bait.”

  The display now showed movement of the Nebula fighters back to Earth and the aliens’ second echelon back to join the rest of their battle group, out beyond the asteroid belt.

  “At this point, we launch a counterattack, first with a massive torpedo barrage, and then with a follow up attack by the heavy artillery on our converted transports and Milo’s alien fighter with the EMP cannon. We have very good information on where they’ll reassemble beyond the asteroid belt and also where all their sensors and mines have been placed to protect them from this sort of attack. It’s pretty clear that the asteroid-buster torpedoes that the nations gave us won’t make it all the way to the targets. They move too slowly and will be picked off by the aliens’ plasma and x-ray guns. But the detonations will create enough noise to mask the gravity bow waves in front of our torpedoes. They’ll move at very high relativistic speed and will reach the targets before the enemy can respond. We were able to put thermonuclear mines and
precision targeting systems on five small runabout ships, and we adjusted the controls to let them go at 99.9% light speed to predefined points where they’ll detonate right among the alien formation. We’re aiming for the battleship, and we should be able to take out anything that’s nearby. Our engineers had a bit of a challenge here, but it’s all been done, and we even had a chance to test one of the ships at that high speed. If it had a weapon, it would have detonated within half a kilometer of where we set it to go off.”

  “So these torpedoes will destroy the rest of that battle group?” Billingsley asked.

  “Probably not. We want to get the battleship and maybe one or two of the cruisers. But we can’t bank on that, so we have a second part to this phase of the plan. Like I said, we’ll use the converted transports and Milo’s ship, plus twenty five fighters to attack immediately after the torpedoes go off. This will be synchronized very precisely with the torpedoes, so the ships will drop from high relativistic speed several seconds after the last torpedo detonation, and they’ll be at firing range immediately. They’ll target the largest ships that haven’t been put out of action, and as soon as the aliens reorganize and start to fire back, the transports and Milo will back away. The fighters will form a rear guard for them so that they can retreat out of range of the largest alien cannons that remain active. This should take out some of the other big ships and will also let us calibrate the remaining long range firepower.”

  The display now progressed to show the planned engagement, including a tabulation of the estimated results in terms of probabilities of destruction for each of the ships in both the alien and Nebula forces.

  Haverford let the audience look at the tabulations for a few seconds, and then he continued. “We’re pretty confident that we’ll get almost all of the smaller ships and even most of the heavy ships, but one or two of them might survive even if they get hit by a nearby torpedo detonation or by our artillery. The heavy cruisers and the battleship have pretty strong shields, and if they’re powered up in battle-ready strength, those ships might be damaged, but they’d probably still be alive. Even the lighter cruisers have pretty good shields, so some of the enemy ships will survive. That’s what we show here in the most likely estimate. We could lose half of my fighters while they protect the transports and Milo’s ship as they retreat, but we probably won’t lose any of our ships with the heavy artillery, and that’s important for our defense of the approaches to Mars.”

  “So, you expect these to be our first casualties?” Billingsley asked.

  Before Haverford could respond, Gladys interjected, “not exactly the first,” and she pointed to her bandaged arm.

  “Right,” Haverford continued. “Gladys’ injury was the first of many more that we expect once the aliens get organized and move toward Mars. Up to now, we had a big advantage by being able to know exactly what they were going to do. But from now on, all we really know is their overall strategy and the outline of their operational plan. That still gives us some advantage, but it will fade pretty soon, especially once they realize that we’ve been reading their mail. And they’re pretty intelligent. It shouldn’t take them much longer to figure that out.”

  Haverford then changed the display to describe the next phase of the defensive plan.

  “What we’re trying to do is simply delay things until the biological agents can have their effect on the fleet. If we can do that, we’re almost sure to defeat what remains of their force, if they even choose to fight us at that point. They might just lick their wounds and pick up and leave.”

  “I don’t think that they’ll just leave, even if the biological attack is successful,” Brad replied. “My team has intercepted a lot more of their message traffic, and our people who are interrogating the captured aliens have also learned a lot about their intents. They seem to be absolutely committed to taking Earth as their home world. They think that this is probably the best, maybe only, good prospect within at least fifty or sixty thousand light years.”

  “Well,” Haverford replied, “if our biological attack is successful, we should be able to hold them off even if they do try to continue their attack. Remember that the main body of their force is still docked at the fleet, so most of the crews will probably be infected, and their high command will also be hit with the plague when it spreads across their fleet. That should weaken them enough for us to counter anything that they try, as long as they don’t take control of Mars and the region around it. If they can set up those big guns and that platform ship, we’ll have a problem, but otherwise, we should be able to handle things.”

  “OK,” Billingsley said. “So what are we going to do to prevent them from doing that?”

  “First off,” Haverford continued, “we’ll reassemble the fighters and artillery ships in the region near Mars to provide some resistance as they try to move in. I have twenty five fighters stationed on the two moons to provide protection for the artillery ships if they have to retreat. They’ll also be available to join the fighters engaging the aliens if necessary. Our forward deployment will be between Mars and the alien battle group, which will probably be reinforced by ships that had been docked at their main fleet.”

  The display showed the simulated maneuver of the Nebula ships from their attack positions outside the asteroid belt back to the region around Mars. The display indicated that only half of the fighters were expected to make it back, but they were joined by the twenty five that had been waiting on Deimos and Phobos.

  Haverford gave everyone a few seconds to look at the display and then went on with his explanation. “You can see that we’ve positioned the artillery just beyond the orbits of the two moons, arranged as a shield in the direction that we expect the aliens to come from. Our fighters will stay behind them and off to the side so that they have a clear field of fire. When the aliens move in, we’ll start our artillery barrage, and then the fighters will go out to meet them, hopefully without having to contend with that battleship or any of the heavy cruisers. Milo will go with them, with his EMP cannon on the alien fighter. The transports will retreat, trying to keep out of range of the alien plasma cannons, but staying within range for their own heavy plasma cannons. They should be able to duel with anything but a battleship.”

  “What happens if your force fails to turn them back?” Billingsley asked.

  “We then fall back to keep out of range of their long range guns,” Haverford replied. “Then we try to give our team on the surface as much support as we can, but at that point they’ll pretty much be on their own and will have to play it by ear. They won’t be able to repel a strong alien invasion force, so we’ll lose Mars eventually, but if we can hold them off long enough for the biological agents to do their job, we can win even if we lose Mars. Our artillery ships will still be able to hurt them until they get their big guns set up on Mars, but after that, we’ll have to retreat back to Earth and launch our thermonuclear weapons against their fleet. We might be able to penetrate their sensors and defensive systems if we launch multiple waves of nuclear strikes, one after the other in close sequence. But we don’t want to get to that stage for obvious reasons, so our delaying action has to work.”

  Billingsley looked at Gladys. “Are you sure that it’s going to work?”

  “I’m positive. I just don’t know how long it will take. But it will work. We have at least three pathogens that we know should be nearly 100% lethal and a few others that are almost as bad. The only thing that we don’t know is how long the incubation will take now that we understand that their metabolism is a lot different from ours.”

  “But it will work?”

  “Yes. Of that we’re absolutely certain.”

  The planning session ended on that note, and everyone filed out of the room and went off to do their work. Brad and Brendan went together to the shuttle that would take them to Nebula Ops, where they would complete the preparations for the defense of Mars.

  *

  The team on Mars had welcomed the arrival of Colone
l Haverford’s five special operations soldiers and was just preparing to discuss how to engage the aliens in direct combat when the first of the big problems occurred. It took everyone by surprise and was a clear indication of the difficulties from now on in dealing with an enemy that wasn’t as perfectly predictable as in the past.

  The assault on Earth by the robotic ships started as expected, but the course that the ships flew wasn’t precisely as expected from the messages that Harry and Yuri had intercepted. The problem seemed to be in the interpretation of the ingress route that they’d take at near light speed, before dropping to low speed and starting to fire on Earth. The attack was supposed to come from an angle of approximately 30 degrees above the Earth’s orbital plane, but the aliens apparently used a coordinate system based not on Earth’s orbit but on the average of all the planets, weighted by their size, so Earth’s orbital plane was averaged into the result well below the weighting given to the planes of Jupiter, Saturn, Uranus, and Neptune, and the ships arrived at an angle off by several degrees. Since the minefield had been deployed to present a very dense shield at the location where Nebula’s planners expected the ships to appear, it was off sufficiently to degrade its effectiveness and more than just one or two of the ships survived the blast.

  Nebula’s fighters engaged the surviving robot ships, and a relatively quick battle did manage to destroy all of them before they could take shots at Earth. But in the exchange of fire, two of the Nebula fighters were destroyed and another three suffered damage. The damaged ships could probably be repaired in a few days and could return to battle, but this was the first fight in which Nebula’s forces had taken any damage at all, and it was a sobering wake-up call for what lay ahead. The loss of comrades in the fighters that were destroyed also dampened the high morale and enthusiasm that had built up since the wildly successful operation against the first battle group.