| Future Civilization and Starflight |
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| The Sun, Gateway to the Stars The energies required for starflight are incredible. To power a starship at speeds over a mere 1% c, an incredibly large fusion drive that could handle energies equal to those released by nuclear bombs every second for years on end would be necessary. Just use the kinetic energy equation KE=mV^2/2 to find the energy required to propell the starship and know that 4.12x10E15 joules equals the energy of a one megaton bomb. There might not be any blast or shockwaves in the vacuum, but there will be intense radiations that will super heat the reactor so radiation reflectors and cooling systems will be necessary as well as heavy shielding for the crew. The energy must be released in controlled quantities over long periods of time. The passenger hull will also be located on a boom hundreds of meters long since radiation density decreases with distance. Science fiction movies like Star Wars and Star Trek make star flight look easy-as easy as dog fighting in airplanes and naval maneuvers at sea. In truth, star flight will be an Olympian task. Multi-generation star arks that take centuries to cross the interstellar abyss come to mind. Colonizing the Oort Cloud might be also be possible. Humans and robots could use materials from Kuiper Belt Objects, also called Trans-Neptunian Objects, comets that exist by the billions, perhaps trillions, and possibly rogue planets in the depths of space to build space colonies and use hydrogen from the ices of comets and other worlds beyond Pluto for fusion energy. Eventually they could reach the limit of our Oort Cloud which extends about 2 ly from the Sun and cross over to the comets of the Alpha Centauri system. After centuries, perhaps millenia, of "leapfrogging" from comet to comet they could reach the Centauri system. Multi-generation star arks powered by fusion and braked with mag-sails could reach the AC3 system in 100 to 200 years, but these will have no appeal to men and women who want to visit other star systems in their own lifetimes. Although there might be people who try to make the crossing in multi-generation arks or even in biostassis, faster interstellar travel is called for. Unless we can learn to manipulate the Higgs field and eliminate inertia and zero-point energy, we must harness incredible energies. Fortunately, we have a source of energy-the Sun. It radiates 3.8x10E26 watts of energy per second. Only a tiny portion of this is needed to propel a starship up to half the speed of light or faster by using laser sails or particle beam mag-sails. For instance, to propell a million ton starship to 66%c at one G will take (200,000,000 m/s)/9.8 m/s2= 20,408,163 seconds or 236 days. The energy required (ignoring relativity, discussed later) will be: KE= 0.5 (1,000,000,000 kg)(200,000,000 m/s SQRD)= 2x10E25 joules. We will need to produce (2E25J)/(20 million seconds)= 9.8x10E17 watts at 100% efficiency or tap just 0.00000000258 of the Sun's energy. A square solar collector at Mercury's distance from the Sun would require an area of 10E14 square meters at 100% efficiency or be about 10,500 kilometers on a side. Since silicon solar cell efficiency is about 15% we'd actually need a collector 25,800 km on a side. Solar thermal systems using aluminum foil reflectors to concentrate light on boilers to run turbogenerators could actually be more efficient. If we assume that the efficiency of the system for transferring energy to the ship (particle accelerators, power conditioning equipment, the efficiency of the mag sail, etc.) to be only 10% we need a solar collector 81,650 km on a side. We could build 100 of these to power independent beams. Each would be 8,165 km on a side. Such engineering should not be impossible in centuries to come. Olympian Engineering The task seems worthy of the Gods, but that's what primitive men think of today's engineering feats until they've learned more about science. We will need propulsion beams, lasers or particle beams, the size of asteroids that can handle staggering energies without frying. I'm talking banks of lasers or particle accelerators from a few to hundreds of kilometers wide and of similar length. We will need sails of equally large proportion. If the energy of the beams is spread out over a sail area of many thousands of square kilometers, the sails won't vaporize despite the enormous energies of star flight. Instead they will just be highly illuminated. For instance, (9.8E17)/(10E14)=9800 watts per square meter on a sail 10,000 km by10,000 km. At Earth's distance from the Sun 1350 watts falls on each square meter. So this is 7.23 times brighter; not enough to fry a highly reflective sail. The sails might be made of sheets of reflective material just a dozen atoms thick, or they might consist of loops of superconducting cables tens of thousands of kilometers wide that generate magnetic fields that catch rivers of relativistic plasma fired out of particle beam accelerators; or the magnetic fields may hold on to a bubble of plasma that catches the particles fired out of projectors. I favor magnetic sails or plasma sails similar to M2P2 and particle beam projectors because magnetic sails can produce one hundred times the thrust per sail mass as a light sail according to Dr. Robert Zubrin who envisioned the magnetic sail with Dr. Dana Andrews. Particles might come from the hydrogen and helium ions of the solar wind and corona if possible or magnetic scoops might siphon up material from the surface of the Sun. The mass will be collected by giant magnetic scoops in solar orbit and accelerated to relativistic velocities to propel the ships. If this proves to be ineffective or downright impossible it will certainly be possible to use mass from captured comets or harvest gases from the atmospheres of Gas Giants, Titan or Venus with skyhook pipelines. Venus is close enough to the Sun to base solar energy collectors there. Out around the Gas Giants or Titan we would need enormous reflectors to concentrate light on solar panels or turbogenerator boilers. While captured comets or the atmosphere of Venus might be best to supply mass to the beams in our solar system, if gas giant planets exist in orbit around hot A type stars like Sirius which is 23 times brighter than our Sun at about the same distance as from our Sun, we could still tap sufficient amounts of stellar energy to power the mass beams. The magnetic fields of the sails can be discharged by diverting the superconductor current into a bank of lasers on the ship that sweep away particles ahead of the ship after reaching cruise velocity and charged back up again to brake in the tenuous plasma and magnetic field of the galaxy to brake the star ships when they approach their destination. To power the mass beam projectors, we will need massive solar energy complexes in space. We can picture Dyson shells partially surrounding the Sun consisting of thin film silicon photovoltaics on a substrate of a fairly high melting point metal reinforced by carbon fibers. Perhaps diamond monofilament or carbon 60 nanotube fibers thousands of miles long will exist when this extraordinary engineering is performed. The shells if suspended by solar pressure above the solar equator would not block out light to the rest of the solar system. At 10 million miles from the Sun, they would not even be visible to human eyes. However, we won't need anything this grandiose just for star flight. See: Interstellar Shuttles The star ships will be small space colonies with gardens, homes, ponds, trees and more. People will not be confined to tiny ship cabins like prisoners for years on end. They will continue to live normal lives while en route. Electrical power will come from fusion reactors. Shield vehicles will travel ahead to prevent collisions. The Oort Cloud will be mapped in stupendous detail by radars and robot probes centuries before the mighty star ships set sail. We won't crash into any comets! See: Collision Avoidance. I call the solar energy collecting complex with mass beam projectors a NODE. Eventually, we will build other NODEs around other stars of the galaxy and tap their energy to propell our ships to other more distant solar systems. Our first stop will be the Alpha Centauri tri-star system. Here we will find not one but three solar systems to explore. Since Alpha Centauri A, a yellow G-type star like our Sun and Alpha Centauri B, an orange K-type star are on the average about as far apart as Uranus is from our Sun, we are likely to only find planets close to their parent stars. We don't know if these two stars formed this close together or if they were more distant once and were captured by each other's gravity. If the latter is true, there might have been gas giant planets ejected into the nether realms of the comets that certainly orbit these stars given our theories about solar system formation. Proxima is about one tenth of a light year from the two main stars. It should be interesting also. As we expand into space it may someday become worth while to build star ships near bright stars like Sirius and use their abundant energy to send beamrider ships on their way on courses that fly-by many stars. Instead of braking the ships with mag-sails in the tenuous interstellar medium or on mass beams emenating from the target star as we will do in the early phase of galactic expansion, small pods carrying humans in hiberation will brake into the system as this will require less energy and time than braking the whole ship will. The ship will be deflected with mass beams to set it on target for another star for a lower energy cost than would be paid if the whole ship was stopped and propelled back up to cruise velocity at say 0.5c. Pods carrying hibernating humans and androids could be propelled up to 0.5c to rendesvouz with the star ships and travel to more remote destinations. Eventually the ships will reach a distant bright star NODE where they will brake with mag-sails, be rebuilt or cannibalized and new ships built, and then sent back through the winding route they followed. When and if this beamrider network emerges, presuming we don't find better ways of interstellar travel, efficient rapid two way travel throughout the colonized stars will be possible. We cannot breed like rabbits forever, a matter I will discuss in more detail later, and our job as good stewards of the galaxy is not to swamp the universe with humans. We might want to increase the range of life by bringing it to lifeless worlds. Naturally, our first job is to protect Mother Earth and preserve life on this garden planet. We will probably build O'Neill type space colonies, cities on the Moon and perhaps we will terraform Mars in the next 200 years. In the course of our interstellar explorations we will establish life on other worlds, but we must not interfere with life that already exists out there, excepting mere bacteria. Will we build clouds or disks of space colonies in numerous solar systems using the local resources of asteroids and airless moons? Perhaps a number of solar systems where no native life exists will be transformed this way, but not the whole galaxy. We might terraform numerous Mars-like worlds. We might build space colonies in the lifeless Oort Cloud. There's no telling how far we could go. From Slaves to Star Voyagers This fantastic engineering, done with the help of androids with human intelligence, robots of lesser intelligence that can be programmed to do complex tasks as do bees, wasps, termites and other insects; ultrapowerful computers and the technological developments of the next few centuries, will be no more difficult for the humans of tomorrow than the building of Roman aqueducts was for the slaves of the past. Before we build multimillion ton vessels at 50%c we will build smaller ships that travel at lower speeds. The first nuclear pulse or beam driven unmanned probes could be launched within 100 years, if we have the will to do that. The first manned missions in ships carrying perhaps 50 to 100 colonists at 50%c could probably be realized within 200 years. With replicating robot mass production and the vast resources of space as well as extensive space industrial infrastructure, fantastic things may be realized. Once we have industrialized the Moon, probably for solar power satellite building and helium 3 mining, progress in space will begin to expand for many other purposes including tourism and scientific research (large telescopes to study planets orbiting other stars, nuclear experiments, particle accelerators that dwarf the ones in operation now, SETI, materials research, etc.). With AI robots and automated factories in space to churn them out as well as millions of tons of material launched by mass drivers on the Moon to asteroidal materials hauled with nuclear pulse driven or mag-sailing freighters, industrial growth in space could become exponential with no Earthly limitations like gravity, rust, corrosion, storms, endangered wild life, indigenous populations, pollution of the biosphere, local wars or politics, pre-existing land claims or even taxes. Medical and Bio-Science of the Interstellar Age Genetically engineered plants might have chlorophyll that has been modified by the alteration of one or two amino acids to increase photosynthetic efficiency. Humans will also be genetically engineered. All hereditary diseases will be overcome. Human digestive systems will be more efficient. The oxidative enzymes of our cells will be improved. This will allow us to digest and burn our food more efficiently, so we will eat less. We will also process the indigestible cellulose out of our vegetables during food preparation and use it for mushroom substrate. Mushrooms will supply excellent protein. We will learn to control our biological desires, perhaps by the use of drugs and microcomputer implants and even ritual practices like fasting, so that we only eat as much as we need, rather than hogging up food and drink and excreting undigested matter that must be eliminated somehow. With vast robotically produced wealth to enjoy we will have better things to do than overeat. We will live in sanitary environs and be free from infectious disease. Our genetically enhanced immune systems will destroy cancer cells, viruses and bacteria before they ever make us ill. We will eliminate all carcinogenic toxins from our diets and environs. We will not sunbathe in UV light and we will shield ourselves from radiation. There will be virtually no disease and no waste of food and farm area. Our free radical scavenging enzymes will be enhanced and perhaps the telomerase enzyme too. We will live for at least 120 years, even a thousand! Advanced surgical techniques will allow the repair of any injury to our bodies. There will be mechanical prosthesis of different sorts. There will also be the personalized cultivation of organs and limbs from cloned stem cells that will not be rejected by our immune systems. Lost arms will be replaced by new arms grown in incubators and surgically attached. We will master the processes of tissue repair and heal any wound. There will be nerve, bone and muscle regrowth factors to stimulate healing. Premature death will be a rarity. Why Fly? We come in peace? Nodes, propulsion beams and Carriers do not break any Laws of Physics, but they do stretch the limits of technology and practicality. Technology is limited by unbreakable physical laws. In the same way that the actions of animals are limited by their bodies (lack of hands, lack of color vision, etc.), low intelligence and powerful instincts that rigidly control their behavior; humans are limited by the laws that govern matter and energy. There are some good things about this. We can build a vault and keep our valuables in it safely because humans cannot penetrate solid metal very easily. If we could walk through walls there would be no security and no privacy. If we were telepathic there would be no security or privacy in our own minds. Likewise, imagine what one man with a phaser could do. And what security would there be if one could beam into the Federal Reserve Bank vault, remove some gold and beam out? If we could travel at warp speed, what would become of the universe? Consider this: If the population continues to grow at about 1.5% per year, in 3000 years there will be 1.5x1029 people, or 25 quintillion times as many as there are alive today. If we could support six quadrillion people in the solar system by mining the asteroids, moons and comets, we would need 25 trillion solar systems in 3000 years. There are only 100 billion stars in the Milky Way, so we will need 250 galaxies! There are about 100 billion galaxies in the universe. At 1.5% per year, we could swamp the entire universe in just 4000 to 5000 years. You can see why I hate to borrow money! Anyhow, unrestrained reproduction combined with intergalactic travel would spell doom for other lifeforms out there, especially when us peace loving, generous humans have phasers and photon torpedoes to gently persuade them to submit to our moral laws or die! We must live for more than unrestrained satisfaction of our biological urges, including reproduction and aggression, if we are to expand into space. The Speed of Light and other physical laws will keep us in check, and that's good. It makes the game of figuring out how to work with what Nature has provided us with more interesting. We might discover natural "wormholes" in space or even figure out how to open wormholes, but those to have limits, so we aren't going to drill our way throughout the universal fabric of space and time and ransack all of creation! Although the existence of transcendental powers is scoffed at by hard core scientists, we must wonder how is it that consciousness exists at all, what lieth within the subconscious, if there is a collective unconscious, why mass has gravity, why gravity can slow time down, why mass increases and time slows down at relativistic velocities, why mass has inertia, etc. There is much about this universe of four dimensions that we have yet to understand, and only by increasing our intelligence or "raising our consciousness" will we ever be able to comprehend it all. Life extension would give more of us time to learn about all the mysteries of science and mathematics, if we could afford the education or if education was free or at least provided at a nominal cost. Although science can peer into our brains with various devices and we can communicate with each other through various media from sonic waves of speech in the air to email, nobody has ever seen through the mind of another. I think, therefore I am, yet I have no evidence that anything more than a mass of electrical impulses exists within others and the possibility exists that I am the only conscious entity on this planet while everyone else is merely mimicry of the life I know that I posses. I am alive, but you might merely be a complex player piano or a vast bundle of reflexes that has no awareness but simply seems to. There is no proof that God exists. There is no proof that You exist. And I cannot prove to you that I exist. Are we then to approach life in a totally depersonalized state of mind, indifferent to the dubious entities that claim to exist in other human bodies? Or must we perform an unscientific act of faith in each other's existence? And if we can do that, can we not have faith in something transcendental? And if there are super-physical or transcendental powers, might some "Benevolent Force" in the universe grant them to us only when we are ready to use them responsibly? Or when we need such powers to survive? Or when the good they yield to the righteous is far in excess of the evil that can be done by the wicked? So many people fear Pandora's box, it's a wonder we still have fists. Envy has more to do with the rejection of science by the ignorant and the demons they worship than any reasonable sense of caution. Greed and vanity/pride has more to do with the misuse of science than any inherent non-existent evil in radioactivity, gunpowder, knives, stones or fists. Anybody who wants to go back to the stone age can just strip naked and go out into the wilderness. When winter comes and they have to hunt their own deer, they'll develop a more favorable attitude towards science and technology! As for anti-gravity and FTL travel, who knows? The wonderful thing is that we can see how to improve the human condition and reach out into the galaxy with AI, robots, biotechnology, nanotechnology and mega-scale space engineering, and it's far more interesting than black magic. |