While studying Project Orion, both at Central Arizona College as well as outside of it, I have had a great deal of assistance. I would like to recognize those who have aided me in my study of Orion.
Dr. Mel Heaps for his being my mentor, as well as his advice on how to go about studying Orion, and his help with some of the more complicated Physics formulas.
To Dr. Temenoujka Fuller for her advice in some of the formula that did not exist, and her aid in helping me to come up with the model I tested Electromagnetic Pulse with.
I have had the privilege to talk to George Dyson via email. George Dyson at the time was getting ready to publish a book on Project Orion, and graciously emailed me an advance copy of the book, which assisted my research of Orion greatly.
Thank you to Ginny Atkinson, who was always willing to listen to my ideas, even if they were a bit over her head sometimes.
Last, but not least, thanks to those people on both the Yahoo Project Orion Club as well as Nuclearspace.net for their assistance in collecting photos, as well as introducing me to the topic of Orion. Without them I would not have a project.
Throughout the course of history, many strange and unusual ideas have been discussed. Many of the strangest are in the attempt to fly. People have attempted to fly with devices as simple as a few boards with feathers attached to it, balloons filled with hot air, even specially shaped wings that miraculously allow one to fly. You may have noted that the second and third are a hot air balloon and an airplane. There have been tanks filled with liquid hydrogen and oxygen, both of which are highly explosive, such as in modern chemical spacecraft. There have even been ideas of large cannons to fire a person to the moon or farther, such as Jules Verne theorized. However, if you were to look at the patent of Dr. Stanislaw Ulam filled by the AEC in 1959, you would see perhaps the strangest idea of them all, to launch a spaceship by launching nuclear bombs out of it’s back end repeatedly. The idea was called at that time Project Orion.
Stanislaw Ulam was one of the members of the Manhattan Project, which developed the world’s first Atomic bomb. He, like many of the Los Alamos staff, was an immigrant from Nazi Germany who wanted to help the war effort in the United States. However, he was unable to serve directly on the battle lines because of age. He asked a colleague of his how he could help with the war effort. From this person, he was directed to Los Alamos. He was of great help to the effort there. In 1946, after WWII was ended by the Atomic Bomb, he started to theorize of a spacecraft that was propelled by nuclear bombs. He believed it could not be manned, because there would be too great of a momentary acceleration in an extremely brief period of time. He thought of it momentarily, but he decided not to really develop anything out of it.
Dr. Theodore Taylor, a noted physics, also had quite a reputation for his work on the Atomic Bomb. However, he did not work on the bomb directly. He is the originator of the design for the largest, the smallest, and the most efficient fission bombs ever, not to be confused with the thermodynamic bombs of later years. His crowning achievement, the SOB, or Super Oralloy Bomb, was the largest fission bomb even till this day, exploding with the force of roughly 600 kilotons of TNT. This is still smaller than most thermodynamic bombs, but when it was originally designed, it would have been big enough to destroy literally any military target in the world. However, its development was greatly overshadowed by the Hydrogen Bomb, which had been successfully tested only a few months before.
Ted soon became tired of working at Los Alamos. He had began to resent the fact that he could get no credit for his work, and wanted to do something that was not classified. The designs for nuclear reactors had become declassified, and Ted had been offered a position at General Atomic. It was there that he met Freeman Dyson, who would have a great deal to do with Project Orion.
Freeman Dyson was perhaps one of the most unique people ever known to the theoretical physics world. He had the ability to spontaneously leap from one thing to another, with little ever lost. His most famous contribution to physics was QED, or the Quantum Electrodynamics theory, which, according to Dr. Temenoujka Fuller, is a theory that deals with the way light and other forms of radiation react with matter. This was of great importance to Project Orion, as it dealt a great amount with trying to energize radiation to create the maximum possible momentum increase possible.
General Atomic gained a great reputation in the 1950’s from what was known as the TRIGA reactor. This was the world’s safest nuclear reactor. It was made in such a way that if one removed the poison rods quickly, which allowed fission reactions to take place without the massive explosion that occurs in a nuclear bomb, the whole structure went sub critical due to a property of matter known as the warm neutron effect, and no longer function. It was a great success, which enhanced the reputations of General Atomic, and most especially Ted Taylor, and Freeman Dyson to the point that anything they theorized could possibly be feasible. It was this that allowed Orion a chance, and not to just be tossed out.
II. The birth of Orion
The day Sputnik was launched, October 4, 1957, was as Ted Taylor describes it in his biography, the most exciting day of his life. He started to see space travel as a reality, and immediately began theorizing different methods to achieve orbit. This led him to begin to thing of how to most efficiently take an object into space. He realized that the Nuclear Bomb was the most efficient thing we had for converting mass to energy in the whole world, and began to design a spacecraft that would use nuclear bombs as a means of propulsion.
Ted Taylor had brought up Stanislaw Ulam’s idea of a nuclear bomb driven spacecraft. The main differences were that he added massive shock absorbers and radiation protection so that it could in fact be manned. The most commonly designed Orion, as George Dyson states in his book Project Orion, is as follows. An Orion spacecraft would have the ability to lift approximately 1000 tons of cargo into space, out of a total of about 4000 tons of launching mass. The total cost was estimated to be sizable fraction of the soon-to-come Apollo costs, which landed only 12 men on the moon and took about 60 men into space. However, Orion would have the ability to carry about 150 people anywhere in the Solar System, the vast majority being dedicated scientists, and land them on any planet of their choice excepting the Gas Giants, or on one of the moons of any planet.
The size of the Orion spacecraft was about a 135-foot circle, about 10 stories high. The exact figures are still classified to this day, because it shows how exact nuclear weapons can become. By quite a large coincidence, this was the about the same dimensions as the library at General Atomic. Ted Taylor often pointed to the library and said that it was the future of space travel, meaning of course Orion. In order to withstand the thrust of the nuclear weapons, the pusher plate would probably have used bags full of gas to contain the force of the bombs exploding behind it. This would work, except in the case of a failure of one of the bombs, in which event most likely the pusher plate would fly off of the back of the ship. The pusher pate was one of the most debated problems of Orion during its time period. According to George Dyson, there was literally dozens of designs theorized for Orion, and probably hundreds more that were never touched upon.
Needless to say, Project Orion wasn’t received very well, although it was actually received better than you would think today. Remember that at that time, the US had never launched a spacecraft into orbit, and they wanted something that would do it. There had been no Viking missions, no Pioneer, no Hubble Telescope, no Skylab, nothing. In fact, NASA did not yet exist. NASA was in the process of being formed, but it still existed solely on paper, and had no basis in fact. The United States had no satellites in orbit, and except for the few days Sputnik remained in space, neither did the Russians. The only things we knew of the Solar System was what we could see through ground-based telescopes, and nothing more.
Orion, in its most researched form, is a 4000-ton ship, 1000 for the ship, 1000 for the pusher plate, 1000 for the bombs, and the last 1000 for payload. It could not land on any planet, so the payload includes many chemical rockets to shuttle people from locations such as the Moon, Mars, and many of Saturn and Jupiter’s moons. It was possible, but seemingly very unlikely, that Orion would touch down on a very low gravity moon. However, it appeared unlikely that the United States would allow the first sign of presence from Earth on any planet or moon be to spew radioactive waste all over that celestial being.
Orion would without a shred of doubt been one of the greatest tools of research ever built. It would have probably collected more data about the Solar System than any other spacecraft in history, as well as soil samples from at least a half dozen different worlds, as compared to our current collection of Earth and Moon rocks. At first it was only a United States effort, but slowly the scientists wanted cooperation between the US, Western Europe, and later even Russia. Today, if an Orion were ever built, it would most likely be the combination of several countries, much like the Space Station Alpha is being built today.
According to Ted Taylor’s biography, a normal fission bomb, such as was dropped on Hiroshima, is shaped in an elliptical shape. This allows the resulting fireball from the nuclear explosion to be in a shape somewhat like a car wheel, so it can cause the maximum damage to an object on the ground. Much heat would be wasted if it were to be shot up. A fission bomb typically includes 5 layers. The outermost mainly a protective layer, but reflects some of the heat from the initial explosion inward, waiting until it can convert the maximum matter into energy. The next layer is of C-4, which is one of the most explosive chemical bombs, and also one of the easiest to shape. This layer is the first part to a nuclear reaction; it explodes simultaneously to implode the ball of plutonium 239. The next layer is a reflective shield, usually made out of Uranium 238, which allows the explosion more time after it reaches critical mass to cause a chain reaction. The next layer inwards is a thin layer of plutonium, shaped again something like a football. The innermost layer contains deuterium and/or tritium, which when heated to extreme temperatures that a simultaneous implosion creates, will fuse together, producing a large surplus of neutrons, allowing the nuclear chain reaction to take place at the exact right time. This is different than the first generation of nuclear bombs such as was dropped on Hiroshima, and was primarily the invention of Ted Taylor.
On the other hand, an Orion fission bomb, or as those who designed them like to call them, pulse unit, is shaped more like a wheel, only very thin. It is classified information, but I believe it is somewhat concave inward, as compared to most bombs being concave outward. It would probably use urea to cause the implosion that would result in the nuclear explosion. Urea is used because this would make the bomb the most efficient it can be, due to urea’s high opacity, which means that it will absorb the most radiation and convert it into kinetic energy, which can be transferred to the spacecraft. Orion pulse units most closely resemble the fission trigger nuclear bombs used in a Hydrogen Bomb, and that is the reason so much is still classified on the subject. A Hydrogen bomb is basically an Orion pulse unit with certain easily light compounds, such as Lithium Hydroxide, pointed at the end of the Orion that is flat. When the fission bomb explodes, it causes the Lithium Hydroxide to fuse together, producing a massive explosion.
Project Orion was first taken on by the AEC, who donated a mere $5000 for its research, according to George Dyson. More important than the money, the contract from the AEC allowed those who were in Project Orion to use classified documents. They started the project, originally with just 3 scientists, Ted Taylor, Freeman Dyson, and Freddy de Hoffmann, who served as a representative to attempt to gain funding for the project much of the time.
The Project Orion staff attempted to go after many government agencies to secure funding. They went after the military research department, who had just formed the Advanced Research Projects Agency, usually shortened to just ARPA, in an attempt to counteract the Soviet space program. ARPA paid $1 million dollars to support it for the year of 1958, and paid the project a total of $2,325,000 total for the development of the project, according to George Dyson. In 1960, ARPA decided that Orion needed to be brought to an organization more important than ARPA. The staff of Orion received funding directly from the United State’s Air Force.
Meanwhile the project’s staff was greatly increased. It grew to a size of about 50 scientists, plus a few engineers. The biggest problem at this time was how to allow a plate of metal to survive the almost impossibly high temperatures that the nuclear bomb would create. They erected a machine that would launch extremely hot plasma at an aluminum plate. Right before a test, a person had mistakenly put 4 thumbprints on the plate. Those thumbprints would have gone unnoticed, but they actually were the most resistant of anything of the plate. Where the man had stuck is thumb showed no sign of the normal destruction, where everywhere else was vaporized. By a contamination of the sample was created a way to protect an object even against the destructive power of the nuclear bomb.
The last great challenge was the shock absorber. The shock absorber must be able to handle pressures of up to 50,000 pounds per square inch repeating it self as much as twice a second for as many times as 2000 times in a row. As George Dyson states, this was never solved during the project. There are at least a dozen different plans all of which seemed to not work. The hardest problem was the possible occurrence of a dud bomb, which had the tendency to separate the plate from the rest of the ship. This was the probably greatest problem remaining, aside from getting continued funding for the project.
The Air Force was a tremendous supporter. They knew that project Orion had some use as for the military, but could not come up with one. In the end this was the death of the Project. It soon became apparent that Project Orion just did not seem to have a use for being a military funded operation, in an era where space travel just did not seem to be of any great importance, at least to travel beyond the moon to show dominance towards the Russians. Project Orion seemed to be more of a civilian project than anything. But the civilian space agency, what would come to be known as NASA, was just barely beginning to be created.
The Air Force continued to increase their support of Project Orion until 1963. In that year, as George Tyson proclaims, Project Orion requested $30,000,000 to continue development, including several underground nuclear tests. The Air Force had a policy that anything over $2,000,000 in any project had to be passed on to the Congress for approval, before the funds could be given. Congress could not see any use for the project as a military weapon, and decided that Orion belonged with the newly formed NASA. Meanwhile, NASA had decided to go to the moon using chemical rockets, and they would not change their mind for anything else, especially a space ship with the possible design flaws of a nuclear bomb propelled spacecraft. However, they agreed to give Project Orion $100,000, on the off chance that chemical rockets failed for some reason. This was in the year 1963. They did not continue funding into 1964.
In 1965 there was a brief period where the AEC, the Air Force, and ARPA agreed to continue funding for the project, as well as allow an underground nuclear test, if NASA would renew it’s support. NASA agreed only on the first use of the nuclear rocket, such as NERVA, that would use a nuclear reactor to spew out some propellant at high speeds. As the Project Orion staff was unwilling and unable to work on nuclear rockets after the glory that Orion promised, then Project Orion ended. Its death resulted not in failure of its principals, but in failing to secure funding from a bureaucracy.
But was Orion even possible? According to George Dyson, about half of the major staff of Project Orion now disagrees with the theory, including Ted Taylor and Freeman Dyson. Their reasons differ greatly from one of the scientists to another. Ted Taylor has since become anti-nuclear, perhaps the most extreme anti-nuclear person in the world at this time. He believes the every gram of Uranium and Plutonium should be tossed somewhere, preferably on a collision course for the sun. Only radioactive isotopes for medical purposes would be allowed to stay. Freeman Dyson now doubts they could have made a pusher plate that would withstand the great pressure of an atom bomb so many times so repeatedly. Many others disagreed for other reasons. The fact remains that Project Orion just doesn’t seem plausible anymore.
Over the years, Orion has changed. It became a fairly popular concept behind many science fiction novels, the most well know probably being “Footfall” co-authored by Jerry Pournelle, a technical report writer on the Orion staff, and Larry Niven. There have been numerous different versions that have recently invented, including the “Mag-Sail Orion”, the “Super Orion” and “Daedalus”. There is even a plan to build smaller Orions, launch them into a point between the Earth and the Moon in which the gravity pull cancels each other out, and use them in case of Asteroids. Each of these are more efficient than Orion, somewhat less dirty, and all beyond current technology. However, they all have yet to be studied in the great detail that Orion was.
I personally revisited the issue of Project Orion in June of 2001. At first I thought it was a ludicrous idea, not suitable for even consideration. However, something inside of me made me continue to do research. This led me to a few serious considerations, of which the main ones were Fallout and Electromagnetic Pulse.
To calculate the damage of fallout, there is a very important number that must first be obtained. This number is the number of rads a person can absorb at very low dosages before dying. It was suspected to be about 100,000 initially, but now is known to be about 10,000. Using this number, approximately 10000 people have died from radiation poisoning resulting from nuclear tests that did not live near ground zero, as George Dyson states in his book.
Now, how does this relate to Orion? It has been estimated that the total fallout of one launch of Orion would be about 1% of the radiation that had been launched into the atmosphere. This can be reduced by a factor of 10 if launched at the Magnetic North Pull. So, totaling everything up, about 10 people would die every time an Orion was launched.
Now, I don’t want you to go thinking that 10 perfectly healthy people would instantaneously die when an Orion was launched. In all actuality, there would be thousands, if not millions, of people whose lives would be shortened slightly, totaling the lives of 10 people. In other words, if one million were affected, it would shorten their lives by about 3 hours. And it is likely that more than just one million people would be affected, lowering the number more.
Notwithstanding, Freeman Dyson, one of the principal creators of Orion was against Orion even at its height until it could be proven that there was only the minutest chance that one person would be killed. The development in small pure fusion nuclear bombs never was developed, so Orion would still be a major cause of radiation poisoning. Still, Orion is not as deadly in terms of fallout as I had first presumed it to be. So long as the area around ground 0 is evacuated, at least an area of 50 miles, preferably more, it would be relatively safe.
VI. Electromagnetic Pulse
Another of my large objections to Project Orion was in the Electromagnetic Pulse shockwave that would result from the use of such a bomb. Electromagnetic Pulse is the affect of nuclear weapons that has a tendency to destroy electronics for a large area. It is caused by radiation ionizing the atoms in a band around the earth approximately 20-30 km high. It is extremely damaging. A 1.4 Megaton bomb launched about 400 kilometers above Kansas would destroy most of the electronics that were not protected in the entire Continental United States. That is a large area. However, Electromagnetic Pulse remains almost untested for small nuclear bombs.
Electromagnetic Pulse was a theory of nuclear weapons that was not tested until the early 1960’s. This was the same time period that Orion was under development; so little research was done on the Electromagnetic Pulse effects of Orion. In fact, George Dyson informed me that he read 6000 pages worth of information on Project Orion to write his book, largely in the form of declassified reports, and that Electromagnetic Pulse was not mentioned on a single page of these papers.
I asked about this question in many message boards on the Internet. However, the best response I could get was “EMP is not significant for less than 1 megaton bombs” from the Yahoo Project Orion club. I believed it was significant, but I was largely been unable to find out a way to test my hypothesis. However, I did get some information, mostly on using a very commonly used and applied physics formula known as the Inverse Squared law, which states that the power of a field or charge or many other things varies inversely squared with it’s distance.
My simulator required a great deal of effort to produce. I had to include issues such as acceleration, figure out where each bomb would be when it exploded, and approximate the damage caused by the Electromagnetic Pulse shockwave. Having little knowledge on converting nuclear force to distance, I had to rely upon flight figures I scrounged over the Internet, as well as a few other places. This was not an easy feat. Web sites, books, reports, all did not like to exactly describe an Orion launch, only giving hints as to what it may do. The details are probably classified. However, I gave this problem serious consideration, and proceeded to design a simulation. I decided to use the most common Orion I read about, the 4000-ton version. I had a few numbers; such as it used 200 bombs to reach an altitude of 125,000 ft. I was trying to figure out the force that it would take the bombs to accelerate the ship at 20 m/s, and did. Then I tried to find a time where it would reach 125,000 ft in 200 bombs. However, I discovered that these results were far from optimal. I decided to rework everything I had to find the most optimal Orion launch, provided that I could only change the time between bombs, and ever bomb would provide a force of approximately 80,000,000 Newtons, which corresponds to an initial acceleration of about 20 m/s2, or roughly double that of gravity. I found that the bombs should be launched in intervals of about 1.1 seconds. In the end with many hours of long work, I came up with the Orion Simulator, which is on the CD that came with this paper.1 The simulator was based off of Newton’s laws of gravity as well as Newton’s third law of motion. It is true that Newton’s laws of gravity are no longer held to an absolute truth, but they are useful for determining the force of gravity between objects that are not microscopic.
That was all for the physical displacement of Orion. I also had to calculate the damage from the Electromagnetic Pulse. This again was not an easy feat. I took estimations of the power of EMP based off of nuclear test of Starfish Prime during Project Dominic. My main concern with this was the figures I had were 1.4 thermonuclear megaton bombs. I would be basing my figures off of a twenty-kiloton fission bomb. To attempt to resolve this problem, I first guessed that there was a linear relationship between bomb size and power of Electromagnetic Pulse. This is probably false, but I don’t have any better information. Second of all, I used known figures to guess how powerful. According to the Federation of American Scientists, a 1.45 Megaton bomb in Project Dominic did severe damage to a radius of at least 800 miles when launched at a height of 248 miles. When converting these into metric, I have a 1.45 Megaton bomb launched from a height of 400 km and affecting a radius of about 1300 km severely. This is not perfect, because these were done on the Pacific islands, where electronics are still to this day not very reliable. Then I assumed that fission bombs created about the same amount of gamma rays as a thermonuclear bomb, and that about the same amount were ionized and created the electromagnetic pulse shockwaves. This one was really stretching the truth; in all actuality fission bombs create more radiation, and thus do more damage, than thermonuclear bombs. And lastly, I took no consideration at all of the Earth’s magnetic field lines, which can potentially greatly influence the sphere of influence of Electromagnetic Pulse.
I still had a few problems. I needed to make sure that the explosions occurred in a range where nuclear explosions could take place, at a minimum altitude of 30 kilometers. Finally I proceeded to execute the simulation. I tested in circles around ground zero of one kilometer. I started these figures at one kilometer from ground zero, and continued to the range of about 8000 kilometers. This is quite a bit farther than is destructive by Electromagnetic Pulse, but this is what I determined to be the maximum area that has even the slightest effect of Electromagnetic Pulse, as it’s the maximum area that is in line of sight. I had it put a guessed value for Electromagnetic Pulse destructiveness. I know that it is not perfect, but it should be close enough for my purposes. I said a number of 100 would be destructive to most systems somewhat, and the higher the number, the more destructiveness would be affected.
n order to calculate the radius of are affected, I needed a few more formulas than could be provided by my previous experience. I tried to look them up, but could not find anything. So I drew a diagram, and used the laws of trigonometry and geometry to calculate these formulas. I have included these formulas as well as the formulas I used to calculate EMP below.
ote that c=distance from the center as determined by arc length, a=altitude, E=electromagnetic damage index, P=power of the bomb, measured in kilotons, D=damage of EMP on a specific area, d=distance between the ground and the point of the explosion of the bomb, is the Earth’s Radius, and is equal to , and V is the light of sight from altitude a. Formula 1) is the distance between a point on a circle and a point above it, given the arc length from the closest point to the circle. Formula 2) expresses the linear relationship between bomb size and EMP damage, formula 3) is the inverse squared law of Electromagnetic Power, and formula 4) is the calculations of line of site.
In the end, I determined a radius of 276 kilometers, or about 170 miles, would be affected. The full results are available in the Orion.dat file on the CD2. Note that the first number is the distance from ground zero, the second the number of times an Electromagnetic burst damaged the area, even if only minor. The third number is the maximum damage index. The last is the altitude where the maximum damage explosion occurred. That is a large area. There are not many areas where this would be safe, and probably the best would be the magnetic North Pole. The North Pole is convenient for several reasons, but mostly because it is isolated and reasonably easy access from the sea is possible. I will discuss this more later.
VII. Other Problems
Closely related to Electromagnetic Pulse is an unnamed affect of nuclear weapons that has a tendency to destroy satellites, especially those in low orbits. Henceforth I will refer to this effect of nuclear weapons as Space Electromagnetic Pulse. Although the two subjects are not completely related, they are close enough to share that kind of a name. Most military satellites are protected against Space Electromagnetic Pulse, but most civilian satellites are not. Note that Space Electromagnetic primarily affects spacecraft in low Earth orbits. That means your phone services/cable TV would probably. However, there are still a great many satellites that are very important if not critical in low Earth orbit, not the least of which is the International Space Station. There are several thousands of satellites that would be affected by this devastating affect of nuclear weapons. To do some kind of testing on this, I tested for bombs blowing up in the Van Allen belts. To my surprise, none did. So while space Electromagnetic Pulse may damage something, it would not be a critical blow to the space industry.
Another problem I faced early was what if something wrong happens? What if a whole bunch of bombs fail? When I built my simulator, I threw in a random chance that the bombs would not work. I had the ability to make it so any fraction 1 over a number of bombs did not work. Orion would make it beyond the Earth’s escape velocity with 800 bombs, even with as many as 1 in 10 failing, at random. It would not crash until a factor of something like 1 in 3 is considered, and then there was only a very slight chance of incidences. All in all, it is a very stable design, not prone to many accidents causing it to fail. The number of nuclear bombs that have not gone off successfully is much less than one in ten, and is probably more around the range of one in a hundred, or even less than that.
When I started this project I was hoping to come up with a result that would encourage me to be completely unsupportive of Project Orion. However, as I studied, I found that there are so many pros to an Orion launch, and most of the cons are minor, especially providing certain selections in choosing a site for the launch of Orion. Providing that Orion can create nuclear bombs that produce very little to no fallout, and it is launched at the Earth’s Magnetic North Pole, then I support a ground based launch of a Project Orion spaceship. In order for me to fully support it, I would request it to be a development among all industrialized nations, such as the Space Station Alpha It must also carry replacement satellites or the tools and materials to construct them in case anything is destroyed by the space electromagnetic pulse effect, and is launched at a time where it would be the least bothersome to man-made satellites already in orbit. In other words, its time would need to be at a moment when it is most easily able to avoid satellites, especially the Hubble Space Telescope and the International Space Station.
My reasoning behind the Magnetic North Pole is as follows. All of the magnetic lines come to the poles, so they can’t trap radiation nearly as much as with a launch closer to the equator. It is easily accessible by sea, and very little inhabited. It would reduce Electromagnetic Pulse, fallout, and Space Electromagnetic Pulse. As a whole it would work perfectly for an Orion launch.
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1 Will be available on the internet at http://www.geocities.com/brp13/orion.html
2 Will be available on the Internet at http://www.geocities.com/brp13/orion/ in the same package as the simulator.