Retribution (Shaitan Wars)

by Sudipto Majumdar

  If however the Shaitan warship wanted to travel at 4% the speed of light instead of 2%, that is double the speed, it would need almost 120 thousand tons of fuel, which is a ridiculous amount even for the Shaitans. The size of their ships would reach unmanageable and perhaps unbuildable levels. The amount of fuel required spirals out of control after that.

  For example to reach 7% light speed, requires one and a half million tons of fuel and 8% is almost unachievable however much fuel you add to the ship. So clearly this approach of carrying fuel has an absolute practical limit to the speed that can be achieved. With the improved efficiency that we expect from our engines after we assimilate the Ka-let technology, we would be able to improve on the maximum speed slightly, but the upper limit would still stay.

  To put numbers behind what I mean, we expect that after we incorporate the improved engine efficiency, we could build a ship weighing about 20 thousand tons, the same as that of a Shaitan warship. This ships of ours would be able travel at a maximum speed of 2.2% the speed of light, by using 40 thousand tons of fuel. To help cut down the acceleration time and also to provide redundancy for such a long journey, we would strap on 4 Nautilus class engines to this ship. Such a ship would reach Alpha Shaitan in just over 12 years. This is definitely an improvement over the Shaitan warships, but not by much.

  One of the quirks of space travel is that you do not use more fuel to travel farther… you use more time. More fuel is used only to travel faster, which reduces time. Thus in the space race with the Shaitans, endurance of the species during space travel counts as much as the technology of the species.

  We have no idea how much agony the Shaitans go through during their 16 to 20 year travel here to Earth, although their stasis technology definitely helps keep their body younger. We have no idea of the Shaitan social relationships, so we don’t know if they miss their fellow beings that they have left back in their own world.

  However I can say this with certainty, that even with our improved technology, a 12 year journey one way would definitely turn a human crew mad, despondent and unfit for combat. Even if we could put them into stasis the entire time, which does not look likely with the current technology we have, few would be willing to go on such a venture, where the earliest return time is 25 years, more likely around 30 years, almost all of their productive adult life.

  So you see ladies and gentlemen, despite us having a slight edge in speed, the Shaitan still wins because its species can endure the journey, which they have proved by coming here twice. In fact the crew of TC-2 from Beta Shaitan has shown the ultimate endurance by travelling for 30 years and still fighting us tooth and nail on the Moon.

  The Shaitans will come here again and again attacking us and wearing us down, while we will not be able to go to their home world and retaliate. In the long run that does not bode well for our chances of survival. Clearly we need to be able to reach their world, which means that we have to be able to travel faster. This means that we have to rethink the very way we get our propulsion on the ships, because the current one of carrying fuel is not going to get us there.

  This is where the new technology of the Ka-let ships comes into picture. We may have got only one new innovation, but what an innovation it is. Let me start explaining the innovation by making a statement of fact that some may not be aware of. No part of space in our galaxy is empty. It just appears so because of the extremely low density of material, primarily gasses that exist in most of space.

  Our galaxy on an average has one hydrogen atom in every cubic centimeter of space. That is one single atom, not even a molecule of hydrogen, which consists of two atoms. These are the hydrogen atoms that were created at the big bang. For 13.7 billion years, these individual atoms have been floating freely in space. They have not even encountered another hydrogen atom in all this time to form a molecule. The hydrogen atoms are distributed so sparsely in the universe.

  The 1 hydrogen atom per cc of space is an average as mentioned earlier. There are regions in our galaxy which are far denser, like the heart of our galaxy, where the density of hydrogen atoms can reach as high as a 1000 atoms per cc. There are also sparser regions, like the space between the spiral arms of the galaxy, where the density drops to 0.1 atom per cc.

  Our local neighborhood till a few billion years was an interstellar nursery like the one you see today in the horse head nebula, where new stars are formed. It was filled with gas clouds that were dense. There were trillions, in places millions of trillions of hydrogen atoms per cc. After stars like our sun, Alpha Centauri etc. formed, the solar wind of the various stars pushed the gas cloud aside. According to the science logs of the Ka-let ship, which made the actual journey and kept records, this region is now left with only 144 hydrogen atoms per cc on the average. Still it is far denser than the average across the galaxy.

  The first question that comes to the mind of any engineer, is how such sparse quantities of hydrogen would be able to power a spacecraft that requires tens of thousands of tons of hydrogen. Not just any hydrogen, but the isotopes Deuterium and Tritium. Deuterium is only 0.0156% of the total hydrogen that occurs naturally in the universe. Tritium is even rarer.

  The ratio of Deuterium to normal hydrogen is 1:15600. To extract one ton of Deuterium, we would have to harvest over fifteen thousand tons of hydrogen. This seems an impossible task, till one realizes the amazing amount of distance a long voyage to a star covers.

  If we were to set up a collection mechanism in front of a spaceship 10 kilometer in radius, which I will shortly explain how the Ka-let technology achieves, then the ship would have collected hydrogen from a volume of over 6x1030 cubic meters or 6x1036 cc. That is 6 followed by 36 zeroes. That number is so huge that it compensates for every other number.

  It takes about 6x1026 atoms to make one 1 Kg of Hydrogen, and there are just about 106 atoms per cc in our neighborhood of the galaxy. Yet the ship is able to collect over a billion tons of hydrogen. As mentioned earlier, Deuterium is only 0.0156% of this, rest has to be discarded. Still we get 165 thousand tons of Deuterium for every light year travelled.

  Deuterium is only half the fuel, the other half is the rarer Tritium. Tritium is radioactive and decays into Deuterium with a half-life of 12 years. So Tritium is unlikely to be found anywhere in space in reasonable quantity to be harvested like Deuterium. The Ka-let have used an ingenious method to obtain Tritium.

  Of the gasses floating in the interstellar space of our galaxy, 91% is hydrogen and 9% is helium. Thus for every 10 atoms of hydrogen, there is one atom of helium. For the Ka-let process a particular isotope of helium, helium-3 is bombarded with a neutron and we get two atoms as a result. One is a normal hydrogen atom, while the other is Tritium. This process actually has been known to us for over a century, and is a fairly efficient process even for us to make Tritium on Earth.

  The catch is that helium-3 is rare compared to the other isotope helium-4. Only one in 8000 atoms of helium is the isotope helium-3. As a result not enough Tritium is collected to match the amount of Deuterium. The Ka-let supplement the helium-3 collected with helium-3 produced in the fusion reactor. As you know ladies and gentlemen, helium-3 is the by-product of nuclear fusion generated in our reactors along with the energy.

  We and the Shaitans eject helium-3 as ion plasma for propulsion in our ships and throw away the rest into space as waste. In theory if we were to accelerate our ion plasma close to the speed of light, then its relativistic mass would increase, and we would require much less helium-3 for propulsion, which could be used to generate tritium.

  Ours and Shaitan ion plasma ejects helium-3 for propulsion at 43%, which means that our propellant He-3 is only 1.1 times its rest mass. We never bothered with this figure because we have always had excess He-3 for which we had no use. We can make the ion plasma eject at 99.5% of light if required and make the He-3 ejected 10 times its mass at rest. This will enable us to conserve most of the He-3 produced in the fusion.

  Thus we have no shortage of Tritium, o
nce we have enough He-3. The only downside of generating Tritium from He-3 is that it takes about 10% of the energy produced by the fusion reactor to be ploughed back into making the He-3 required for the next cycle of burn, thus reducing the reactor’s output effective output by 10%. As we shall see this is more than compensated by the higher speed of the ship.

  So for every light year travelled, we have 224 thousand tons of Deuterium, and a matching quantity of Tritium, making a total of 448 thousand tons of fuel. To put that in perspective, a fully fuelled Shaitan warship carries 45 thousand ton of fuel. On a journey from Earth to Proxima Centauri, a distance of 4.23 light years, we can collect nearly 1.9 million tons of fuel.

  From the logs of the Ka-let, we know that they made the journey from Proxima Centauri to our solar system in about 21 years. We still don’t have the technology to beat that time, but we can come pretty close to it. To put this discovery in perspective ladies and gentlemen, what the Ka-let technology has gifted to us humans is the stars themselves. They have opened up the stars. We humans can become an interstellar spacefaring civilization with this technology.” Benedict paused from his lengthy discourse and reached for some water.

  Despite the fact that Benedict had not indicated that he had finished his deposition, the Japanese councilwoman spoke up. “I am sure that is very exciting Mr. Parsons, but that still gives us no more idea about how it will help in winning this war. How does it help in reaching Alpha Shaitan?”

  Benedict finished his glass and looked at the councilwoman with a slightly sheepish look. “I must admit council woman, that with respect to Alpha Shaitan, the improvement in travel time as a percentage is less, although I am sure every little bit helps. This is really a long voyage technology, which comes to its own as you travel a few light years or more.

  I can assure you however that this technology still gives us an edge when it comes to reaching other Shaitan worlds, like Beta Shaitan and further distant Shaitan worlds. It is an edge that will let us strike their home worlds a lot more easily with better logistics than they can ever hope to achieve while striking Earth.

  Again to put some numbers behind my assertion, let me start with Alpha Shaitan and from there on it only gets better. Alpha Shaitan is a quarter light year away, so we can expect to collect only about 110 thousand tons of fuel during the journey. The same proposed human ship of 20 thousand tons I talked about earlier, could now travel at 4.8% the speed of light and reach Alpha Shaitan in just under 8 years, about four and a half years earlier than with the conventional technology. That is over 8 years shorter than the fastest Shaitan warship.

  However I am going to strongly propose that in this new class of ships we install 8 of the reactors. I know that this sounds preposterous right now, when we have produced so few reactors. I am however betting on the fact that with each passing year, our capability and capacity to build these reactors will increase exponentially, and that number will not look so preposterous in a few years.

  If we install 8 reactors instead of 4, then the acceleration of the ship doubles and we can reach Alpha Shaitan in less than 6 and a half years. I know that 6 and a half years of continuous journey is unprecedented in human history, but there have been crews and ships in the 16th and 17th century who have sailed for longer on their way to circumnavigate the world.

  However the total return trip time is still 13 years, and giving allowance of a military campaign would probably mean a total campaign time of 14 to 15 years. Unfortunately ladies and gentlemen, this is the best that can be done with the technology we have right now.

  The comparison gets only better with the more distant Shaitan home worlds, from where the Shaitans are likely to get reinforcements. For example Beta Shaitan is a third of a light year away from us. Our ship would take just over 8 years to reach that world, which is 13 years shorter than their fastest warship, which took over 21 years to reach Earth.

  To take the comparison to the extreme, we know that the Shaitans wiped out the Ka-let and most probably took over their world. We have seen the characteristics of the Ka-let home world. It is too good and earth like for the Shaitans to have passed it over. We could in theory strike that home world if we had slightly better hibernation technology, and were able to convince people to go on a 21 year one way trip. The Shaitans however have no hope of sending reinforcements from that world to Earth. It would take nearly 208 years for them to undertake that journey.” Benedict looked at the councilwoman and hoped that she was satisfied with his answer.

  The chair of the council however spoke up to remind Benedict that he had glossed over the actual technology that lets a ship collect individual atoms of hydrogen floating freely in space. “Being an engineer myself Mr. Parsons, I am very skeptical about this magical technology. Unfurling a sail like device 10 kilometers in radius, that is 20 Km in diameter, that can withstand collisions from micro debris travelling at 20% the speed of light seems like a tall order.”

  “And you would be absolutely right in your skepticism Mr. Chairman. As an engineer, if I didn’t know better, I would have been skeptical as well. We were lucky in that the computers in the engineering section of the Ka-let ship were almost fully functional and we were able to recover maintenance manuals as well as designs of most parts of the ship including the harvester.

  It was important because the Ka-let ship will never fly again, so there was no way to actually deploy the harvester to reverse engineer it. We had to learn everything about the harvester from the manuals. We have slowly started dismantling the folded up harvester mechanism that had been tucked inside the ship. This will help us validate and actually build a prototype harvester.

  Before I get to your structural concerns on such a large and potentially flimsy piece of mechanism however, let me first address the physics and the chemistry behind the harvester. The harvester is not some kind of a funnel that channels gas into a collection tank. It would be more helpful to visualize the harvester as a giant circular flypaper designed to catch individual hydrogen atoms.

  Some of those atoms are ionized, meaning their single electron has been stripped off the atom making them positively charged, while others have their atoms intact. There are also a very small number of hydrogen molecules i.e. two hydrogen atoms in a chemical bond as H2, as we see hydrogen normally here on Earth. The flypaper has different strategies for each of these cases.

  The ionized atoms are fairly easily and reliably caught using negative electrical charge, and according to the Ka-let manual, the collection efficiency is over 99.99%. The electrically neutral single hydrogen atoms as well as the hydrogen molecules are caught by means of chemistry, but engineered at a nano-scale. A fairly well understood chemical process called hydrogen bonding is used to bond these hydrogen atoms and molecules to elements like nitrogen, oxygen and fluorine. All of these elements are strongly electronegative and bond very strongly with hydrogen. Oxygen being the most well-known, to form H2O.

  The resulting hydrogen rich chemical compounds are filtered in that nano-chemical factory, using a process for separation of normal hydrogen and Deuterium. The chemical process itself is run of the mill, which ladies and gentlemen you can find yourself if you search the internet. What is amazing about the filtration process is that it is being done at the molecular level by the nano-cells. This is a feat of engineering we have not been able to achieve till now, and this will be one of our biggest engineering challenge as we try to replicate this technology.

  The filtered molecules containing Deuterium are transferred to another cell in the nano-factory, where energy is applied and the reverse chemical process separates out the hydrogen catching molecule like oxygen and nitrogen. The oxygen and nitrogen is reused for catching more hydrogen. The hydrogen, which is now in gaseous form inside a closed capillary is sent back to the hub, to be collected inside the ship’s tank.

  Now that we know the nature of this hydrogen catching flypaper, let me come to the structural question that has been vexing you Mr. Chairman. A 10 Km radius struct
ure, i.e. 20 Km diameter structure sounds outrageous here on Earth, but not so in space. This is primarily because there is no gravity to weigh down the structure. However that does not mean that the structure faces no stress.

  The structure faces stress throughout the period that a ship is accelerating or decelerating. The Ka-let have developed simple but effective ways to alleviate the structural stress. The structure begins unfurling out like an umbrella being built from scratch. First 12 support spines radiate out of the sides of the ship all around the circumference equally spaced, much like the spines of an umbrella radiate out of its hub.

  These spines however are not rigid. They are flexible and foldable, which fold out of their stowing mechanism and stretch like a cable to a length of nearly 10 Kilometers. These cables are however hollow, and contain a fair amount of nano-machinery inside them. One of the things that these hollow cables house is an ion plasma guide tube, which is negatively charged.

  A certain amount of ion plasma from one of the engines is routed to these ion plasma guide tubes running through the cables. All along these cables are outlet nozzles for discharge of ion plasma. Nano machinery controls the amount of discharge from these nozzles such that the cables accelerate by the same amount as the ship. This keeps the cables neutral in terms of feeling acceleration, and hence weightless. In addition some amount of the ion plasma is discharged at the ends in such a way that the cables remain taut despite minor perturbations along the web that it will spin.

  This entire process takes less than an hour according to the Ka-let manual. Once the 12 main spinal cables have gone taut, nano-machinery is pumped through the cables, which emerges from various points on the length of the cable. These nano-machinery starts growing to reach the neighboring spine cable. The whole process must look very much like a spider spinning its web.