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“Borders: From the First Sumerians to the Last Starfighter” © 2022 by Jim Beall

“Origins of the West African Launcher from TCG Files” © 2022 by Andy Presby

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Origins of the West African Launcher from TCG Files
Andy Presby

CONTAINS PROPRIETARY INFORMATION OF THE TENNESSEE VALLEY INTERSTELLAR CONGLOMERATE
— TCG INTERNAL USE ONLY —
ALL PATENTS PENDING

Form TCG1116-B: Annual TCG Employee Crazy Idea Competition
Proposal #: 3214
Proposer: Omer Ehrlich, Intern
Current Management Rotation: Oral Hygiene Products
To: John-Philip Jeffy, CEO TCG
Title: REDUCED COST SPACE LAUNCH SYSTEM

Benefit of Proposal: The space between the Earth and Moon is filled with a variety of spacecraft performing many functions vital to modern society. The sheer number of spacecraft, the range of orbits they cover, and the diversity of their activities have outpaced predictions of even the most optimistic of space enthusiasts from before the Second Space Race. This abundance challenges the space industry’s capability to resupply, repair and provide other services to in-orbit customers. While large reusable heavy lift rockets have provided the most economic way to move high volume payloads to orbit for a generation or more, that delivery method is suboptimal for multiple point orbital deliveries. This proposal identifies a new system capable of reliable repeatable launch of payloads up to one ton into any Earth-centered orbit on-demand to meet this need and propel TCG to the forefront of this emerging market segment.

Motivation for Idea: If we can do this more cheaply, we can make a lot money. Or, we could offer the transport for much less and make a lot more orbital industry economically viable.
Getting material into space inexpensively has long been the goal of the space industry. “Once you get your ship to orbit you’re halfway to anywhere” has been a truism of space travel since the 20th century. It remains true today. The essential problem of getting off the Earth is a matter of throwing something high enough and fast enough that when it falls back down, it overshoots the Earth. See Diagram One below.

Diagram One: Getting to Orbit
The hard part is “throwing” your spacecraft that fast. An object in stable orbit around the Earth goes anywhere from eight to ten kilometers per second (km/s) depending on the height and shape of the orbit. That is in an ideal world with no air friction and where we instantly teleport our spacecraft to the right height at the right speed. In the real world, other influences make our vehicle lose speed and make getting into orbit harder.
These are primarily:
•	Gravity losses as the Earth’s gravity pulls on the vehicle the whole way up
•	Air drag for the portion of the flight that goes through the atmosphere. (It is important to note that the densest part of the atmosphere is down at sea level, and total losses due to air drag drop off as we start our trip to space from higher altitudes.)
•	Any other maneuvers needed to get into the orbit we want
These losses add up and mean that getting to orbit actually means being able to go 9 to 12.5 km/s.
The other thing that makes getting to space hard is the fact that we still use rockets to do it. Rockets have to carry everything with them that they need on their trip. This includes all their fuel and the oxygen needed to burn that fuel. A given rocket carrying a given amount of payload with a given amount of fuel and oxygen can get to a given speed by burning all of it. That speed is called the rocket’s “velocity increment” or “delta vee.” If we want to go faster with that rocket pretty much all we can do is carry more fuel and oxidizer to go with it. This however buys us into diminishing returns, because every kilogram of fuel and oxidizer we add increases our gravity losses and makes that new propellant less effective at giving us more speed.
Looking at this we see a few places where we might be able to make a space launch using rockets easier. The first is that we could launch from as close to the equator as possible. This would give us an extra boost of speed from the Earth’s rotation. This is why many nations try to build their space launch complexes as close to the equator as possible, and some companies still launch from ships at sea or airplanes that fly down to the equator. The next would be to launch as high up in the atmosphere as we could to reduce air drag. The third would be to keep your vehicle as light as possible. A way to convert air into fuel or oxidizer on the way up thru the atmosphere would help. Any way to add speed to the vehicle that didn’t require it to carry more fuel would also be a great help.

Proposal Overview: It turns out that there is a way to do all of the things above and this proposal submits this method in accordance with Reference 1. It was first proposed in the latter half of the 20th century, as many good aerospace ideas seem to have been. A number of authors thought of the idea of using a magnetic levitation rail up the side of a mountain to assist an airbreathing, rocket-propelled vehicle in achieving orbit. [See Reference 2 below. Legal review pending on TCG acquisition of any needed IP.] A sled on the rail carries the vehicle, and lets it go as high as possible to reduce the amount of air drag. Further reductions in air drag could be realized by enclosing the rail in a large tube and evacuating air from it. The speed that the rail imparts to the vehicle will allow it to start its engines and proceed to orbit after release. The fact that the rail, sled, and (most importantly) their big and heavy electrical generators are left on the ground means that the vehicle can get its first kilometer per second or two of speed effectively “free” which will significantly increase the amount of payload a given vehicle can loft.
Military missiles, aircraft, and even some launch vehicles have integrated hypersonic technology. The following sections describe each component in more detail. Please see Diagram Two for an overview.

Diagram Two: System Overview
Maglev Rail and Sled (“Launcher” and “Sled”): The magnetic levitation (maglev) rail and its associated sled are the parts of the system that stay on the ground. Their job, as stated above, is to impart as much velocity as possible to the vehicle in order save fuel and increase delivered payload mass to orbit. The site of the launcher requires a tall (>2000 meters) mountain formation, good local power infrastructure, and access to multi-modal transportation options to enable payload transportation and transshipment of goods returned from orbit. Access to nearby airport facilities is desirable to allow returning launch vehicles to land at the launch facility for transportation cost savings. Access to other air traffic facilities down range from the launcher is also helpful to provide abort options in case of failures on launch. It would be ideal to identify locations near the equator to reduce the amount of fuel that vehicles must burn reaching the equator and maximize payload to orbit under ideal conditions.
The launcher takes the form of a linear accelerating rail likely ten or more kilometers long built up the side of the selected mountain. Control, vehicle maintenance, payload processing, and office facilities are located at one end of the rail where ready vehicles can be placed on it. The rail must smoothly run up the mountainside with a minimum curvature and no “bumps” to reduce the lateral forces and shocks that a vehicle experiences during launch. It will likely be necessary to elevate the rail above the ground for this reason. The rail should be partially or fully enclosed to minimize environmental wear on associated power handling equipment. Farther up the launch path, where vehicles would be going faster, it would be beneficial to fully enclose the rail and include a pumping system to reduce air pressure and thus drag. This enclosure could be above or below ground.
The interface between the rail and the launch vehicle would be a sled capable of being levitated and accelerated by the magnetic levitation rail, while holding the launch vehicle in place, surviving the forces involved for the roughly 20-30 seconds a typical launch would entail, releasing the vehicle safely at the correct time, and then being slowed down by the rail for return to the processing facility and reuse. These requirements are novel but conceivable as scaled up application of the technology in electromagnetic catapult “shuttles” used today on aircraft carriers. It should be noted that the rail does not end at the release point but needs a “decelerator’” section necessary to slow down the sled for retrieval. This section can be much shorter (perhaps 1 to 2 kilometers long) because the sled can presumably be built to withstand larger forces than the launch vehicle. Thus it can be slowed down more rapidly than the whole assembly was first accelerated.
One of the reasons that a maglev-assisted space launch system has not been built on Earth to date is that this concept was first proposed when magnetic levitation and electromagnetic catapults were in their infancy. The raw speed of the sled at the point of vehicle release (1-2 kilometers per second) was difficult to envision at the time. Not only that: the required engineering work to make the rail and sled survive that repeated use reliably, day in and day out, for maybe dozens of launches a day, for years at a time had not been done. Today, however, high-speed electromagnetic catapults are routinely used in naval systems and longer higher speed units are coming online for lunar bases. Reliable magnetic levitation mass ground transit, though still a niche application, is much more common and has operated safely for decades. It is true that no one has built one of these up the side of a mountain yet, but the civil engineering of this system is within our reach.

Highly Reusable Airbreathing Aerodynamic Hypersonic Launch Vehicle (“Vehicle”): The vehicle is at least as significant an advance over the current state of the art as the rail. The integration of hybrid hypersonic engines into a reusable winged aerospacecraft means that the vehicle, once lofted, can economically fly to the equator to get the maximum benefit from the Earth’s rotation. It can also maneuver using its airfoils and airbreathing engines to achieve any desired orbit most economically. Finally, its airfoils and airbreathing propulsion allow return to a conventional landing strip near the launcher after re-entry using minimum fuel. This offers a flexibility unparalleled by the large conventional reusable pure-rocket vehicles that currently dominate the up-mass service market.
The airbreathing aerodynamic reusable hypersonic launch vehicle takes advantage of several technologies that were immature or only conceptual at the time this idea was first proposed. But the payoff will be worth it:
•	Carbon composites: Advances allow reliable integrated cryogenic storage tanks for use of the most mass efficient propellant combination available (hydrogen and oxygen) while retaining the strength needed to survive launch, atmospheric flight, reentry, and landing loads reliably and repeatedly.
•	Additive manufacturing: Advances in industrial fabrication techniques make integrating denser metal structural elements and heat management technologies into carbon composite airframes feasible.
•	Boundary layer manipulation: Our current understanding of plasma physics makes it possible to manipulate boundary layers to further reduce shock and drag while enhancing thrust.
•	Hypersonic propulsion: The perfection of the shock induced combustion ramjet (shcramjet) [3] permits reliable hypersonic flight above Mach 12. Rocket-based combined cycle modifications allow the same hardware to act as a rocket in space. Magnetohydrodynamic kinetic energy bypass technology permits the use of highly reliable supersonic turbojets under hypersonic conditions and even extraction of electrical power from the airflow [4]. These advances all enable a small number of engines to operate all the way from sea level to space.
•	Integrated oxygen liquification: Advances in Stirling engines and oxygen separation and liquification techniques allow the vehicle to top off its oxidizer tanks while “cruising” the launch site. This maximizes payload to orbit.
This flexibility, of course, comes with a cost: complexity. As in all launch vehicles, every gram of mass will need to contribute the maximum possible benefit to the system as a whole. The propellants won’t just be used to make the vehicle go but will need to help cool the leading edges of the nose and the wings. Structural spars and skin surfaces won’t just hold everything together but will also contain heat pipes to also help keep the vehicle cool. Boundary layer manipulation and clever use of the engine MHD bypasses may allow the vehicle to perform some maneuvers without moving vulnerable control surfaces in hypersonic airflow. Putting all of the above technologies together will be a challenge . . . but one fit for modern aerospace engineers.

Powering the System: The maglev launcher will draw a substantial amount of power to accelerate the vehicle and slow down the sled. This power can be drawn from the local grid if the site is in an area with adequate power infrastructure. However high power electrical grids with large capacity (gigajoule-scale) pulsed power storage facilities spaced along the rail will be necessary to achieve useful launch speeds. Even more power is demanded if we wish to produce our hydrogen on-site using either electrolysis or methane pyrolysis.
One of the difficulties with these kinds of electromagnetically-assisted launch systems has always been that they are best built up the sides of naturally occurring mountains. These do not tend to have the needed power infrastructure nearby. Furthermore, the kind of pulsed power required for launcher operation is difficult to transport long distances in wires from places where the power infrastructure might be more robust. Simply running large new power lines from dedicated pre-existing power plants is unlikely to be economical. Dedicated local power infrastructure will therefore be needed.
Wind and solar, while often more available in mountainous terrain, also often require the clearance of large amounts of local ecology to get the amount of power needed. The high power levels required by the launcher exacerbate the traditional weakness of these sources: intermittency. Energy storage for a single launch is already large and expensive. Power storage for multiple launches at night or when the wind is calm becomes prohibitive. Fossil fuel powerplants still face substantial investor bias in the West and the fact is that fuel prices have been steadily increasing over the last century. The easiest solution is generally small modular nuclear fission reactors, but these facilities, while safe and reliable, remain expensive today. They will work but another alternative would be desirable.
Geothermal technology may provide the answer. This technology is centuries old. Pockets of heat underground can be used to drive electrical generators. Modern geo-thermal techniques were pioneered in North America and Iceland. It involves digging deep wells to reach pockets of hot rock followed by directional drilling to embed closed loop piping systems with a working fluid in them that runs through the rock to pick up heat and carry it to turbines on the surface. The temperatures in these pockets are upwards of 500°C and can provide renewable power at a density comparable to fossil or fission power plants and far in excess of what solar or wind could do on the same amount of land. The best thing about this for our purposes is that many mountain ranges sit near large natural geothermal power systems. Indeed volcanic mountain ranges contain undreamed of reserves of such power. Microtremors associated with active volcanic regions would complicate the launch system. Adaptions for that might be possible but are beyond the scope of this proposal. Thankfully a dormant, very tall, near equatorial volcano has recently been purchased by the TCG recreations division: Mount Kilimanjaro.

Conclusions: The time is right to do what our predecessors could not and combine these technologies into a launch system to meet the needs of our burgeoning space economy. I hope Mr. Jeffy finds this proposal suitable for funding and further research.

References:
[1] Fabrice Tchami. "Guidelines for Management Track Internship Idea Proposals," TCG Internal Drive.
[2] John Mankins. "The MagLifter—An advanced concept using electromagnetic propulsion in reducing the cost of space," AIAA 1994-2726. 30th Joint Propulsion Conference and Exhibit. June 1994.
[3] Couture, Dominic & Dechamplain, Alain & Stowe, Robert & Harris, Paul & Halswijk, Wouter & Moerel, Jean-Luc. “Comparison of Scramjet and Shcramjet Propulsion for a Hypersonic Waverider Configuration,” 44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference and Exhibit. 10.2514/6.2008-5171. 2008.
[4] Theresa L. Benyo. (2010). “The Effect Of Magnetohydrodynamic (MHD) Energy Bypass On Specific Thrust For A Supersonic Turbojet Engine,” AIAA-2010-232/NASA-TM-2010-216734, December 2010.

Jeffy: Can we send this kid to a research division?
Chummy: Please, no, boss. The toothpaste guys need this kid.
Jeffy: Fine. But make sure nobody headhunts him away from us.
Chummy: Will do, boss.
Jeffy: What about setting up some kind of research retreat space at Kilimanjaro though? The site is gorgeous.
Chummy: I'll make that happen too, boss.

Andy Presby is a former U.S. Navy nuclear submarine officer and current aerospace engineer with degrees in space systems engineering, astronautics, and physics. This fictional-non-fiction article is set in the world of Joelle Presby’s The Dabare Snake Launcher. Joelle is a former U.S. Navy nuclear engineering officer, a former business consultant, and current spouse to Andy Presby.

Borders: From the First Sumerians to the Last Starfighter
Jim Beall

Borders are all around us, some made by nature, some by man. Below is possibly the most recognizable manmade border of them all, The Great Wall of China.

The Great Wall of China at Jinshanling
Image Credit: Severin.stalder, Wikimedia Commons
But what is a border, when did they begin, and why do we have them?
Intrinsically, a border identifies that the two areas it separates are somehow different. Often each side is a different country, while other times they mark a change in ownership within the same polity.
The earliest documented borders were those in ancient Sumer, located in the Fertile Crescent between the Tigris and Euphrates Rivers. That theirs are the first ones to be documented is not surprising, since the Sumerians appear to have been the first to invent writing (~3500 BC), and thousands of their cuneiform tablets and inscribed monuments have survived. (NOTE 1) Perhaps showing how some things never change, one surviving ~3000 BC tablet (currently in the British Museum in London) details the allocation of beer:

Record of Beer Allocation
Image Credit: BabelStone, Wikipedia
The city states of ancient Sumer shared a common theological pantheon, but the cities were typically built around temples to a specific patron god. The cities grew in population (NOTE 2) and were often at war with each other over the control of barley fields needed to feed their burgeoning populations. One such conflict around 2400 BC is related on “The Cone of Enmetana.”

The Cone of Enmetena (Louvre Museum)
Image Credit: Gary Todd, Wikipedia Commons
The beginning of the inscribed text is what is of interest here, as it details the pre-war border between the city states of Lagaš and Umma:
Enlil, king of all the lands, father of all the gods, by his firm command, fixed the border between [gods] Ningirsu and Šara.
Mesilim, king of Kiš, at the command of [goddess] Ištaran, measured the field and set up a [border] stele there. (NOTE 3)
The wording decrees that the border was not some human secular or military matter, but an agreement between gods, perhaps reflecting the resolution of some god-to-god dispute. For centuries, the borders of the Sumer city states fluctuated with the results of each conflict portrayed as the jockeying of city patron gods within their pantheon.
The Egyptians of antiquity also needed borders, not to formalize changes in farmland ownership but to preserve the existing ones. The River Nile flooded the fields every July-August, leaving a muddy and changed landscape when the waters receded in September-October. The only way to preserve the layout and ownership of farm tracts was to regenerate all the property boundaries every year. Thus, the need for empirically accurate property borders forced the Egyptians (~3000 BC) to create an entire field of mathematics: geometry.
Setting such border markers is not a problem limited to foreign lands in antiquity, however. The American Colonies provide a much more recent and close-to-home example. Between 1632 and 1681, three different British kings (Charles I, Charles II, and James II) issued three conflicting land grants to Cecil Calvert (Second Lord Baltimore) and William Penn involving the lands that would become Maryland, Pennsylvania, and Delaware.
Drawing a consolidated border was deemed near impossible, as it would not be straight, but include arcs, tangents, and even a transpeninsular bisecting line. Border conflicts grew steadily worse until another British monarch—King George III—demanded in 1760 that the parties resolve the dispute. Accordingly, the Penn and Calvert families (William Penn had died in 1718, Cecil Calvert in 1675) hired two expert British astronomer-surveyors. It would take them almost six years and was only possible due to cutting-edge equipment.
The task required inventing a new methodology (NOTE 4) that included astronomical sightings, often requiring waiting out epic rainstorms in tents. Also, to be able to sight down their lines, they had to cut a 30-foot-wide swath the entire 233-mile length. (NOTE 5)
The two left about three hundred stone markers along their surveyed lines. (NOTE 6) Most marker stones contained a “P” on the side towards Pennsylvania, while the opposite side had an “M” for Maryland. Every fifth mile, a larger “crownstone” was placed with the Penn family coat of arms one side and the Calvert family coat of arms on the other.
       
Mile Markers Images Showing North and South Faces Crownstone
Courtesy of Eric B. Gladhill (NOTE 7)

Image Credit: Steve Fernie,
AlbinoFlea, Creative Commons (NOTE 8)
The surveyors were Charles Mason and Jeremiah Dixon, and the border would become known as “The Mason-Dixon Line.” It has been called a technical achievement akin to the Moon landings. (NOTE 9) Despite being resurveyed several times with steadily improved equipment including satellites and GPS, the legal border remains the straight lines between where the 18th Century surveyor pair placed their stones.
Comparing the Mason-Dixon Line with those two ancient ones reveals startling parallels. Much like the Sumerians, the border was decreed by one king to resolve differences between other kings, and specified humans were ordered to place the markers. Like the Egyptians, Mason and Dixon had to invent a new methodology for border calculation.
The borders discussed so far have consisted of lines drawn between markers. Many others, both modern and ancient, have been physical barriers, as was the Great Wall of China. The purpose of such borders is not merely to identify a change (such as ownership) but to enforce it. These types of borders are expensive to construct and maintain, however, and so are generally built due to a need to enforce the change, with defense the most common historical reason.
Barrier borders do not simply enforce change, however. They create change. Consider perhaps the greatest barrier border on our planet: the Himalayas:

Orbital View from NASA Landsat 7 Satellite
Source: Wikipedia, Public Domain
Caused by the collision of two tectonic plates that began about fifty million years ago, the mountain range is of such height and length that it obstructs weather patterns giving the northern side very different weather than the southern side (note in the above image the green to the south versus the brown to the north).
It turns out that human barrier borders have analogous effects. Consider another famous wall from antiquity: Hadrian’s Wall in Britain, commissioned by that Roman Emperor in 122 AD to be the northern border of the Empire. The Romans were master builders, and the three Legions assigned the task took only six years to complete the seventy-three miles across the width of Britain. Much of the wall remains today and is a very popular tourist attraction and hiking route.

Image Credit: Steven Fruitsmaak
Source: Wikimedia Commons
Rome invaded Britain (“Britannia”) in 43 AD and conquered much of it by 87 AD. Efforts to complete the conquest of the northernmost areas were largely unsuccessful. (NOTE 10) Hadrian’s Wall was intended to protect the southern, “Romanized” lands from the northern barbarians. As can be seen in the image below, much more than a simple wall was involved. Small fortifications (“Milecastles”) and much larger forts (NOTE 11) dotted the entire length.

Map of Hadrian’s Wall Showing Defense and Civilian Sites
Image Credit: David Simpson and Tangled Worm (Note 12)
Thousands of Roman soldiers garrisoned Hadrian’s Wall from 122 AD to 410 AD. Support personnel, like farriers and farmers, well outnumbered the soldiers, and entire villages sprung up around the forts on the southern side of the Wall. In contrast, the northern sides near the wall were empty of habitation by the unconquered tribes. Thus, like the Himalayas, the landscape was markedly different on each side of the Wall.
That is not the only change created by Hadrian’s Wall, however. The Romans recruited soldiers from all over the Empire, but units were never used where they were formed, lest the effect be the training of revolutionaries. Instead, they were always deployed far from home. Records have identified most of the military units (Cavalry Roman Auxiliaries) who staffed those forts: (NOTE 13)

Fort Name	Soldier's Origin	
South Shields	France, Iraq	
Wallsend	France, Belgium	
Newcastle	Germany, Britain	
Benwell	Spain, Germany	
Rudchester	Germany	
Halton Chester	Hungary	
Corbridge	Spain	
Risingham	France, Germany, Switzerland	
High Rochester	France, Spain	
Chesters	Spain	
Carrawburgh	Netherlands	
Housesteads	Germany, Belgium	
Chesterholm	Belgium, France	
Great Chesters	Belgium, Spain, Switzerland	
Carvoran	Syria, Croatia	
Birdoswald	Romania	
Bewcastle	Romania	
Castlesteads	France, Belgium	
Netherby	Spain	
Stanwix	France	
Burgh by Sands	Germany, Algeria/Morocco, Netherlands	
Drumburgh	unknown	
Bowness	unknown	
Birrens	Belgium	
Beckfoot	Hungary	
Maryport	Spain, Croatia, Netherlands	

For nearly three centuries, men from all over the Roman Empire lived decades of their lives in Britain as they served in those units along the wall. Many raised families (or otherwise had children) there, making significant contributions to the genetic diversity of the population. Thus, the border called Hadrian’s Wall resulted in some quite unexpected and lasting changes.
Returning to the Great Wall of China, the simple version of history states that the emperors had it built to keep out northern invaders like the Mongols. That is correct, but the full story is much more complicated.
First of all, walled borders existed as much as three centuries (“The Spring and Autumn Period”) before the 250-year long “Warring States Period” that itself ended in 221 BC when one king, Qin Shi Huang, conquered the others. One of the first acts of the first Emperor was to tear down all the separating walls. He did this to extinguish internal borders, remove wall-caused differences, and unify his new domain into a common culture.
Second, Qin preserved the existing out-facing walls and even used the material from the destroyed ones to strengthen and extend them.
Third, many subsequent dynasties built and rebuilt sections of the Great Wall. A complete picture with timelines is presented below.

Image Credit: Maximilian Dörrbecker (Chumwa)
Source: Wikimedia Commons
The map shows the massive scale of the Great Wall not only in distance, but also in time. Hadrian’s Wall was built in six years by three Legions (roughly 15,000 men) and was 73 miles long. Great Wall construction took place over a period of about 2,500 years, involved about four million people, and is 13,171 miles long. (NOTE 14)
The Great Wall had the same effects previously discussed with Hadrian’s Wall, but the scale of the project caused even more changes. According to historians, Emperor Qin sent one million to build the Wall. Of those, about 400,000 died during the project, with many being buried in the Wall itself. Scholars have estimated the total millennia-long total death toll at about one million, and the Chinese referred to the wall as “the longest cemetery on Earth.”
Walls that are not borders can also cause change, some quite unexpected. A potato blight resulted several years of famine in Ireland and Scotland beginning around 1845. The death toll from starvation and related illnesses was immense. Many of the landed gentry commissioned work projects to help feed their local populations, leading to numerous so-called “famine walls,” “famine follies,” and “starvation roads.” (NOTE 15)
Some seventy-five years after construction, one such famine wall would save a fine and historic castle, but not in the “traditional” way.
In the early 1920s, over three hundred of the great houses in Ireland were burned by the Irish Republican Army (IRA). In 1922, when the IRA gangs came to attack and burn down Castle Leslie, the locals denied them access (they even cut their phone lines). The folk pointed to the famine wall around the estate and said the Leslies had fed them all through the Famine Years, and they would not tolerate actions against them. Thus, the building of the wall—not the wall itself—preserved the Leslie home. (NOTE 16)
Famine walls and famine follies (NOTE 17) dot the landscapes of both Ireland and Scotland. The building of each one fed men and their families. Many walls marked the boundaries of fields or estates, while others served no apparent purpose. Among the more famous in this last group is the wall across the Scottish mountain named Suilven. The slope challenges hikers, yet workers somehow moved and set heavy stones in a perfectly functional (but useless) wall all the way up the crag, across it, and back down again.

Suilven Famine Wall
Image Courtesy of Shane Younie (NOTE 18)
A Demilitarized Zone (DMZ) contains, in effect, a border along its center. The DMZ in Korea is about four kilometers wide and two hundred kilometers long. It was created in 1953 when the military forces of the two warring sides pulled back two kilometers from a ceasefire line. That DMZ is kept generally deserted of human life (NOTE 19), so other life tends to flourish. Among the species making their homes in the DMZ are endangered Asian cranes, black-faced spoonbills, angora goats, Amur leopards, and even bears. (NOTE 20)
Such borders and their effects are not unique to military conflicts. The mitigation measures after the Chernobyl disaster, for example, included the evacuation of about one thousand square miles around the stricken facility. A fence border surrounds the “Chernobyl Exclusion Zone,” which is almost uninhabited. (NOTE 21) Photos of the zone include poignant images of crumbling homes and rusting playgrounds, but other images reveal lush greenery teeming with wildlife, including bears, bison, wolves, lynx, wild horses, and dozens of bird species.
U.S. nuclear power plants provide another example of how Nature takes advantage of manmade borders. Each reactor plant is within a fenced “Owner Controlled Area.” Wildlife flourish there, especially since hunters are excluded by patrols of highly-armed guards.
Such wildlife exploitation of hunter-free zones was previously observed at early federal reactor sites. One illustrative anecdote from the author’s personal experience comes from the USN nuclear prototype facility near Schenectady, New York. Presumably, a bear was sighted in the distance through a fence as it ambled about in the brush. Concerned locals were told by enterprising sailors that a woodchuck had denned near one of the reactors and mutated to great size. The author only learned of the incident many years later during his naval training there after being asked by one earnest citizen if he had seen “Woodie.” (NOTE 22)
Turning to science fiction, the largest border wall in recent filmography may be the 700-foot-tall ice barrier in “The Game of Thrones” HBO television series (2011—2019). The episodes were based on the science fiction-fantasy book series of the same name by George R. R. Martin, with the first book published in 1996. The story’s massive ice structure stretched 100 leagues (~345 miles) along the northern border of what was called, “The Kingdom of the North.”

“The Wall” of Game of Thrones
Image Credit: HBO
According to both the books and the episodes, The Wall pre-dated the current characters, was built by means and people not entirely known, and fends off terrible creatures of legend who live on the other side. Like the Himalayas, the weather appeared to be different on one side than the other. As shown below, this is not the only similarity to other barriers.
Perhaps the earliest (1933) famous “border wall” in science fiction filmography is the one below:

King Kong at the Skull Island Wall
RKO Radio Pictures, 1933
Per the movie and its release information, the wall had not been built by the current islanders. Rather, it was ancient, its builders were unclear, and they had used capabilities completely beyond present local knowledge to create a walled structure far taller and stronger than was possible at the time of the story, and it kept out dinosaurs and other huge creatures. The parallels with “The Wall” in the Game of Thrones are almost exact. (NOTE 23)
Impressive borders are hardly uncommon in science fiction, but the stories reach their peak only after they fail. “King Kong” was no exception!

King Kong Breaks Through
RKO Radio Pictures, 1933
Game of Thrones followed the same pattern:

Breaching The Wall, Game of Thrones
Image Credit: HBO
Another famous wall in science fiction filmography can be found in “Jurassic Park.” Despite significant upgrades in technology, it suffers the same dramatic fate.

Jurassic Park High Voltage Electric Fence	

Tyrannosaurus Rex Breaks Through	
Image Credits: Universal Pictures, 1993	
Basically, border walls in these kinds of stories exist mainly to be breached impressively at a plot-appropriate moment and, until then, serve chiefly as a stage setting for the development of characters as they train, patrol, and cope with boredom. (NOTE 24) The many thousands of Roman and Chinese soldiers stationed for decades along their own walls would have understood perfectly.
Nature has also provided outer space with borders, and science fiction authors have not stinted in using them.
The “discovery” of the first of these was in the 1750s by mathematicians Leonhard Euler and Joseph-Louis Lagrange. That is, they calculated that five points (“L1” through “L5”) around any two large bodies in space would be stable, in that the two known gravitational fields would offset each other. (NOTE 25) As long as objects were placed within a tightly bordered volume, they would theoretically stay there. Crossing the border in any direction, however, would allow one of the gravitational fields to capture the object. The below image shows the locations of the five points, with the relative gravity fields depicted topologically:

Lagrange Points of a Two-Body System
Source: Wikipedia, Public Domain
Space scientists and science fiction writers alike have subsequently used Lagrange points. Several space missions have placed probes and sensors in Sun-Earth and Earth-Moon Lagrange Points, confirming the math. Scientists have also detected natural space objects at the Lagrange Points of several other two-body systems within the Solar System.
The 1975 NASA Summer Study that produced the famous “Stanford Torus” space habitat design relied on using not one, but two Lagrange Points! (NOTE 26)

Stanford Torus
Image Credit: Wikipedia, Public Domain (NOTE 27)
Most of the habitat’s mass would be mined on the Moon and launched at a “mass catcher” at Earth-Moon L2. From there the material would be brought to Earth-Moon L5 for industrial processing into habitat construction. Unsurprisingly, science fiction has featured a plethora of stories of space stations and habitats deliberately placed at various Lagrange Points all over the solar system.
A second outer space border involves black holes. Black holes can be new, created as part of a supernova, or as old as the first years after the Big Bang. They can be ultra-massive (TON 618 is estimated at sixty-six billion times the mass of the Sun) or theoretically comparatively lightweight (primordial ones could possibly be the mass of asteroids). What they all have in common are the strictest borders in the known universe. Specifically, due to their enormous gravitational fields, anything (including photons) that crosses one can never cross back out.

Black Hole at the Center of Galaxy M87
Image Credit: EHT collaboration
Acknowledgment: Lia Medeiros, xkcd
A great many science fiction stories have used various features of black holes, including the time-slowing aspects near the edge of that border. Among the author’s favorites are Gateway (by Frederick Pohl, 1977) and Flies from the Amber (by Wil McCarthy, 1995). In both novels, the characters must make decisions based on the consequences of their emergence from the event horizon at the edge of the border of a black hole.

Gateway
(First Edition Cover)
Image Credit: St. Martin’s Press	

Flies from the Amber
(First Edition Cover)
Image Credit: Roc Publishing	
A third group of outer space borders consists of wormholes. One fundamental element of science fiction is crossing the vast distances between stars and galaxies in short enough time periods for a story to be practical. In many cases, the stories postulate faster than light (FTL) engines, such as “warp drive” or “hyperspace drive,” but exceeding the speed of light violates current theoretical physics. (NOTE 28)
Wormholes have always offered undeniable real-world possibilities because Einstein himself agreed that general relativity suggested they were mathematically possible. The solution is called an Einstein-Rosen Bridge (or Lorentzian wormhole, or Schwarzschild wormhole). As a propulsion method, however, the math is not promising as it also suggests any such wormhole would close faster than anything, including photons, could traverse it. Nonetheless, Einstein’s "blessing" has led to wormholes being used extensively in science fiction as a means of traveling to distant locations in shorter times than light would require in normal space.
In some storyverses, wormholes are depicted as funnel constructs, as in the “Star Trek Deep Space 9” television series. In others they appear as surfaces through which something enters and then exits at another location, as in the movie “Stargate” and subsequent television series:

Bajoran Wormhole, Deep Space 9
Image Courtesy of MorishitaKurumi
(NOTE 29)	

Stargate, SG-1
Image Credit: Richard Dean Anderson
(NOTE 30)	
In contrast to FTL drives that can deliver ships to any location, wormhole-style gates provide science fiction authors with borders that can be attacked, defended, and breached. Ones like Star Trek’s Bajoran Wormhole are natural phenomena whose apertures are permanently locked in place. (NOTE 31) In contrast, the ones in Stargate are created by equipment that is mobile and can be activated or deactivated by the operators. Science fiction abounds with variations on the above themes, and each one creates different border effects and subsequent plot elements.
In one outstanding example, John Ringo’s Into the Looking Glass (Baen Books, 2007) begins with the inadvertent creation of a permanent interplanetary gate in Florida and, hence, a new border to be either exploited or defended. Then more gates begin spawning all over the Earth, seemingly to random planetary surfaces across the galaxy. Each gate creates a new border, including one that becomes a DMZ far more fortified than the one in Korea. Story twists and opportunities abound, including a memorable reprise of the Paul Revere story when aliens invade through a new gate, and a police radio dispatcher takes on the role of the Revolutionary War hero with “rednecks in pickup trucks” the Minutemen. (NOTE 32)
Some story universes combine naturally occurring wormholes with ones that are either caused or opened by devices. One leading example of this is the "Starfire" series, originated by David Weber and Steve White in 1990, which began based on the game system by the same name (created by Stephen V. Cole in 1979). (NOTE 33) The series posits that wormholes come in several classes, with some already “open” that can be defended by “space forts” and other local forces. Other wormholes, however, are closed (but can be opened by technology). Some of those “potential” ones can only be detected from one side, thus posing risk of surprise attacks and the need for rapid response fleets. The combinations of threats and opportunities offer a great variety of both tactical and strategic areas for authors to exploit.

Into the Looking Glass (2007)	

The Stars at War II (2005)	
Images courtesy of Baen Books	
One last form of “gate” in science fiction never defines itself as a wormhole, but simply an opening to another place. It acts like teleportation but, instead of some device or force relocating an item, the object or person simply physically passes through an artificially created opening. One significant early example of this is “The Big Front Yard,” the 1959 Hugo winning novelette by Clifford Simak. In that story, one alien race apparently opens interstellar gates simply as its species’ mission. Once opened, the aliens depart again, leaving the gates open for passage. Humanity only learns of this when the protagonist discovers that his front yard contains one such gate and soon finds himself dickering with various aliens as they peacefully pass through.
John Ringo revisited this theme in his 2010 novel, Live Free or Die,” the first in his “Troy Rising” trilogy. (NOTE 34) As in Simak’s story, a gate is opened by one alien race (who promptly depart to open more elsewhere), and it is then used by many other races. In Ringo’s novel, however, the gate is not a person-sized doorway in a front yard, but a kilometers-diameter one at the Sun-Earth L2 Lagrange Point. Peaceful traders are again the first visitors, but then come mass-murdering thieves in warship fleets with lots and lots of missiles. The gate becomes the Solar System’s border that must be defended at all costs.

“The Big Front Yard” (October 1958)
Image Credit: Astounding Stories/Frank Kelly Freas	

The Hot Gate (2011)
Image Courtesy Baen Books	
Physical barrier borders can be walls or mountains, but distance can be even more effective. The watery width of the English Channel, for example, kept the peoples of the British Isles mostly separate from Europe. After the Romans left, the Saxons invaded, followed by the Vikings and then the Normans. In the end, however, the Channel isolated them and the land absorbed them all. In more recent times, the Channel stopped conquering annexation by Napoleon and Hitler. In the current day, the UK culture has continued to remain so distinct from the rest of Europe that the UK withdrew from the European Union.
As effective as the English Channel has been, the great breadth of the Atlantic Ocean was decisive in the American Colonies drifting culturally apart from England and then allowing the American Revolution to succeed. Science fiction authors have already recognized the likelihood that the vast distances of outer space will inevitably drive self-sufficient off-world settlements to seek independence. (NOTE 35) Human history strongly suggests that cultural divergence would then occur eventually leading to armed conflicts which could produce death tolls not in the thousands or millions, but in the billions.
There may be only two ways polities that sprawl across outer space can maintain cohesive unity. The first is by ubiquitous doorway-style gates that allow so much intermingling that they preserve culture homogeneity. The second is the confirmed existence of one or more dire external threats.
Science fiction authors have written it both ways. When we settle space, let us hope for the first.

NOTES:
1) The Sumerians are not only the first civilization known to use writing, but also wheels, fast wheels (chariots), a legal code, and ships. In the area of mathematics, they may have been the first to be able to calculate the area of a triangle and the volume of a cube. They also identified the five planets visible without telescopes. The oldest known written literature, the “Epic of Gilgamesh,” is from Sumer.
2) The Sumer city of Uruk is generally regarded as the first true city, reaching a population of about 80,000 in 2900 BC).
3) The text on this historical object has been translated many times and, while the wordings vary in detail, they are consistent in substance. The version here is from Wikipedia, with some clarifying words added in brackets.
4) A brief description of the methods they employed is presented here:
https://caf783ab-f4aa-469d-a4ff-2c3a19268299.filesusr.com/ugd/6f029b_b08999b366b24ef79bdbeff2278b80e0.pdf
5) For a comprehensive and wonderfully readable account of their efforts, the author recommends:
Drawing the Line: How Mason and Dixon Surveyed the Most Famous Border in America, by Edwin Danson, Published by John Wiley & Sons, 2001.
6) Few of the original stones remain in place. Many now reside in museums, having been replaced with replicas. The fates of many others, however, remain unknown. While on their way back, the two Englishmen found one already missing. A farmer had dug it up to use as a tombstone for his dog.
7) Eric Gladhill is licensed as a Property Line Surveyor in Maryland and a Professional Land Surveyor in Pennsylvania. He serves as a Director for the Pennsylvania Society of Land Surveyors (PSLS) and is a member of the Maryland Society of Surveyors (MSS). He is currently serving as the PSLS representative to a joint endeavor between these two societies to inventory and document all of the remaining Mason-Dixon stones marking the border between those two states. He is the author of both a book and numerous articles on land surveying:
https://www.amazon.com/Finding-My-Boundaries-Interesting-Surveying/dp/B096TJQNCQ
https://www.xyht.com/author/eric-b-gladhill/?fbclid=IwAR0Mq8pQ2NZvmMI204MFXaCOdSH0P6ICIdZM__meXc3LCs4z7FAWqcka1_A
8) The reason that both coats of arms are visible, rather than being on opposite faces, is because this is one is at the apex of an angle. Specifically, it marks the intersection of the Tangent Line and the Transpeninsular Line at the Maryland-Pennsylvania-Delaware Border.
9) Source: https://www.bbc.com/news/uk-england-40638673
10) One anecdote from Dio Cassius’ Epitome of Book LXXVII provides an insight into the depth of the northerners’ belligerent stubbornness. The Roman historian recounts a conversation that supposedly took place between the wives of Caledonian tribal chieftain Argentocoxos and Emperor Septimius Severus during one set of truce talks. The Empress of the Roman Empire made a disparaging comment about the sexual conduct of the tribal women. The other replied, “We fulfill the demands of nature in a much better way than do you Roman women; for we consort openly with the best men, whereas you let yourselves be debauched in secret by the vilest.”
11) For a detailed video reconstruction of one of the larger forts, the one at Vindolanda, see:
https://www.youtube.com/watch?v=ZnPGb5L7aZ4
12) For more information, including photos, see:
https://englandsnortheast.co.uk/hadrians-wall/
13) Source: https://segedunumromanfort.org.uk/learning/where-did-the-soldiers-living-along-hadrian-s-wall-come-from?fbclid=IwAR3DIk6XQe5668TJR5vMkA0WDDw5mmPTNSD7GFyWF_8oMUCNFxkWS0tarY8
14) In 2012, based on existing research and the results of a comprehensive mapping survey, the National Cultural Heritage Administration of China concluded that the remaining Great Wall associated sites include 10,051 wall sections, 1,764 ramparts or trenches, 29,510 individual buildings, and 2,211 fortifications or passes, with the walls and trenches spanning a total length of 13,171 miles. Some of the wall sections were dirt and many sections have eroded away. The sections most visited by tourists were built or rebuilt during the Ming Dynasty, which ruled from 1368 to 1644.
15) The Victorian Era did not favor giving charity to the able-bodied. This went both ways, as those able to work would often reject charity out of pride.
16) “Christina Leslie ran the [Leslie] Estate in the 1840’s . . . She reduced and canceled farm rents, built soup kitchens to feed many, organized voluntary passage to the USA and Canada and built the 4 mile famine wall around the Estate as a relief project.” Source: https://www.castleleslie.com/wp-content/uploads/2018/03/leslie-family-history.pdf
A powerful recounting of the period, including the survival of Castle Leslie due to its Famine Wall, is presented in the documentary series, “Tales of Irish Castles, Season 1, Episode 6.”
17) Images and descriptions of several beautiful “famine follies” can be found here:
https://www.amusingplanet.com/2017/10/irelands-famine-follies.html
18) Shane Younie is a winner of Scotland’s Moray Mountaineering Club (https://moraymc.wordpress.com/) President’s Award for Mountaineering Achievement. More of his images can be viewed here:
https://www.instagram.com/shaneclimbing/?hl=en
19) One legacy village of about two hundred is allowed to continue farming a portion.
20) The author had personal experience with another DMZ while serving as an engineering officer aboard USS Long Beach (CGN-9) in the Gulf of Tonkin during the early 1970s. The ship’s role was PIRAZ (Positive Identification Radar Advisory Zone) and her long-range radar and TALOS missiles interdicted enemy aircraft from entering the airspace of the Vietnam DMZ. The Long Beach was credited with shooting down two MiGs attempting to breach the DMZ, though not while the author was aboard.
21) A few locals either refused to leave or returned after the immediate emergency passed.
22) On the other hand, the author does not avow knowledge of the characteristics or lifespans of mutated woodchucks.
23) Despite those parallels, Game of Thrones author George R. R. Martin stated in a 2014 that his inspiration for “The Wall” actually came from a visit to Hadrian’s Wall. Source: https://www.rollingstone.com/culture/culture-news/george-r-r-martin-the-rolling-stone-interview-242487/
24) The highly improbable deep space border wall along “The Frontier” in “The Last Starfighter” (Universal Pictures, 1984) was no exception.
25) Euler is credited with identifying the first three, followed by Lagrange the other two. In some documents, this is credited by using the term “Euler-Lagrange Points.”
26) Source: https://space.nss.org/settlement/nasa/75SummerStudy/Design.html
27) The image is a cropped version of the painting by Donald E. Davis, commissioned as part of the NASA study.
28) A special case called Alcubierre Drive is also used because it does not require an object to exceed light speed to achieve FTL displacement. For a brief summary, including the origin of the idea and some of the massive physics problems, see:
https://en.wikipedia.org/wiki/Alcubierre_drive
29) MorishitaKurumi is a gifted artist in Japan. More of her work can be found here:
https://www.deviantart.com/morishitakurumi
30) https://rdanderson.com/index.htm
31) The author’s favorite cinematic portrayal of this type of wormhole is this short video:
https://www.youtube.com/watch?v=mMZbig5t8Ug
32) Page 73, and the author will never look at a “bait and tackle” store the same again.
33) For a full list of Starfire titles, see:
https://www.baen.com/categories/books-by-series-list/starfire-series-by-david-weber-and-steve-white.html
34) The others were Citadel (2011) and The Hot Gate (2011).
35) A few examples: The Moon (The Moon is a Harsh Mistress, Robert A. Heinlein, 1966), the asteroid belt (“Known Space” series, Larry Niven, beginning 1984), Mars (Birth of Fire, Jerry Pournelle, 1976), and distant solar systems (Tactics of Mistake, Gordon R. Dickson, 1971).

Jim Beall (BS-Math, MBA, PE) has been a nuclear engineer for over forty years, a war gamer for over fifty, and an avid reader of science fiction for even longer. His experience in nuclear engineering and power systems began as a naval officer. Experience after the USN includes design, construction, inspection, enforcement, and assessment with a nuclear utility, an architect engineering firm, and the U.S. Nuclear Regulatory Commission (USNRC).