Pillar to the Sky

by William R. Forstchen

  Erich nodded.

  At the bottom Gary drew a curving line, wrote “earth” under the line, then near the top of the board sketched a curved dotted line.

  “Geosynch orbit is the high ground,” Gary began. “That’s 22,236 miles above mean sea level. You understand miles versus kilometers?”

  He looked back at Eva.

  “The scientific community prefers metric,” she sniffed. “Someday the West, with its miles, or statute miles, or nautical miles, or whatever, will get a mission in trouble.”

  Erich chuckled.

  “Point to her,” he announced.

  “Fine, then it’s…” He hesitated for a second, running the numbers through his head. “Geosynch orbit is 35,786 kilometers above mean sea level. Your article proposes the building of a tower with a height of over 35,000 kilometers? Then another 20,000 kilometers beyond that to provide a counterweight? Good heavens, the tallest building in the world is…”

  “At this moment, a radio tower in Moscow at half a kilometer tall.”

  Gary hated metric; to him it always made things sound bigger or faster than they really were.

  “Just over sixteen hundred feet,” he retorted, “a little more than a quarter mile.”

  “So?” Eva replied.

  “You are proposing a tower that is something on the order of nearly a hundred thousand times taller?”

  “Yes.”

  Gary drew another line extending from the curving line representing the earth at the bottom of the board, up to the dotted line of geosynch at the top, and then put a question mark next to it.

  Erich held up his hand.

  “Perhaps I started this backward,” he announced. “Let us start with a positive rather than a negative. Eva”—he paused—“may I call you that?”

  She gave him a winning smile and nodded.

  “Of course, sir.”

  “Explain to our doubting Thomas here the thesis.”

  “Gladly, sir,” and she stood up, taking the blue marker from Gary, the flicker of a grin on her features as if saying, Now I will cut you apart with this!

  “The proposal—as I assume you know, Mr. Morgan, from reading the article—was first suggested by the Russian scientist Tsiolkovsky shortly after he worked out the orbital dynamics of placing a satellite into orbit. At that time, in 1905, rocket fuel of sufficient thrust to fit his dream of space flight had yet to be tested, let alone developed. That would not happen for another thirty years.

  “From this evolved the idea of building a tower at the equator, clear out to what you call the high ground, geosynchronous orbit, that place above the earth where an orbiting satellite will take exactly one day to complete one revolution or orbit, and thus appear to remain stationary. It is indeed the ‘high ground,’ unlike low earth orbits, where a satellite passes swiftly overhead and requires dozens of ground tracking stations, and even at five hundred kilometers up, there is still enough atmospheric drag to eventually slow it down, causing it to plunge back to earth.”

  There was no argument on that point, and Gary simply nodded in agreement.

  “Tsiolkovsky realized that the higher the tower, several things begin to happen. The first, that gravity begins to drop off the farther you are from the center of the earth—that there is an inverse ratio between gravity and distance from the center of the earth’s core. Too many people foolishly assume that everything is weightless in space. Of course, it is not. The only thing that makes it appear that way is that in low-earth orbit you are traveling at nearly ten kilometers a second; you are actually falling around the curve of the earth.

  “But the farther out one travels if ascending a tower, the lower apparent gravity will become, until at geosynch orbit the gravitational pull will appear to be near zero. Granted, the gravitation effect is there—again, at an inverse ratio to distance, which is why the moon stays in orbit and in turn its gravitational pull affects our tides.”

  As she spoke, she started to write out the formula defining this on the whiteboard, forgetting her audience for a moment and making the notations in Russian.

  “Second major point,” she continued as if delivering a classroom lecture, and she was so involved in what she was saying that she did not even look back to see if there were any questions. In spite of her antipathy for him, Gary could not help but feel admiration for her obvious brilliance as she jotted down various equations.

  “The second point is the centrifugal force of the earth’s rotation: attaching the tower to the earth at the equator will help it to remain rigid, imparting at geosynch an orbital velocity as well that will appear to negate gravitation effect. Thus it will at least feel and act like zero gravity, as most mistakenly call that effect for any object in orbit.

  “The tower would not actually end at geosynch but continue on for nearly another 20,000 kilometers, and would be anchored at the far end by a mass, depending upon the weight of the actual tower. So…”

  To his amazement and Erich’s bemused chuckle she reached into the pocket of her slacks and pulled out a string; at one end was attached, of all things, what looked like a lipstick tube. Eva started to turn around, twirling the string, then holding it up over her head, letting it spin in circles, and then to her utter embarrassment, the lipstick container broke free and went flying across the room, nearly hitting Gary.

  “Rather proves your third point, which I assume is angular momentum,” Erich said, laughing.

  For the first time Eva’s icy exterior melted, her little demonstration of centrifugal force having gone awry, and she actually blushed, which softened Gary’s increasingly defensive response to this young woman with such a dynamic presence.

  “Well, uh, sir, that is getting a bit ahead,” she said.

  Erich smiled indulgently for her to continue.

  “With the base of the tower attached to the surface of the earth at the equator and extending out past geosynch orbit, the rotation of the earth itself will provide centrifugal force to keep the tower rigid and erect, unlike a tower only half a kilometer high, which must rely solely on its foundation and massive steel frame to hold it up.

  “And, yes, you just saw the third part—the beautiful part, in my eyes.” There was a growing enthusiasm in her voice. “The tower can also act as a catapult. How much fuel was required by your Apollo and Saturn V rockets to break free of the earth’s orbit and reach TLT, translunar trajectory?”

  “Nearly eight million pounds of fuel burning at over 50,000 pounds of fuel a second.”

  “The tower,” she continued, even more enthusiastically, “gives it to us for free, using the earth’s rotation as the source of energy. We could haul any size payload up to the top of the tower and, once released, the angular momentum atop the tower will be just like a catapult of old throwing a rock. The released object will then head off to wherever we desire, guided by the precise timing of when to release it and a small amount of fuel, a fraction of the amount currently needed to accelerate out of the earth’s gravitational field. This tower could send to the moon the equivalent of a hundred Apollo payloads if we desire, at a fraction of the cost. Using advance drive systems such as Plasma Ion, we could go to Mars in weeks rather than months or years at a cost of hundreds of billions. The cost of one trip to Mars as NASA is now thinking about, if invested into building this tower instead, would give us the path to Mars, with a true transportation system from earth to space thrown in for under the same cost.”

  She paused.

  “Or even beyond Mars. It will open space to limitless exploration, even colonization, of whatever we desire, at a fraction of the cost in energy.”

  “How much would the energy cost to get the object from the ground station, attach it to the tower, and have it climb up to this magical release point?” Erich asked quietly.

  Eva nodded and wrote down another formula.

  “Even using an old-fashioned climber, with wheels attached to the tower or using a magnetic levitation rail, the energy cost will average out to abou
t thirty rubles a kilo.”

  “English, please,” Erich said. “And besides, the ruble is collapsing.”

  She was a bit taken aback for a second, then answered, “About seven dollars per one of your pounds to geosynch.”

  Gary could not help but snort in derision at that one.

  “It currently costs somewhere around $100,000 a pound to loft an object by rocket to geosynch, and you are telling us this tower thing will cut that cost by over 99.99 percent.”

  She nodded again, not thrown by his question or tone.

  “The elevator car or capsule that hauls up the material to geosynch, as it descends, will actually generate electricity, its wheels now acting like a dynamo as gravity pulls it back toward the earth, accelerating as it gets closer. It can thus generate over 90 percent of the electricity it used while climbing up—even more if well designed.”

  She put her whiteboard marker down.

  “Besides moving large objects to geosynch either to place in orbit or catapult to the moon, Mars”—she paused—“or beyond, it would mean that the cost for the average person to go to geosynch, either to work, visit, or even live there permanently, would cost only a little more than a flight from Moscow to New York. It would open space for everyone, not just a select few cosmonauts.”

  For the briefest of moments Gary did feel hooked in by it all; after all, that had been his childhood dream until the age of seven, when it was found that he had a rare form of astigmatism, which meant he could never become a pilot and venture toward the stars; years later, he would be unable to earn a license to fly even a Cessna or Piper a hundred miles solo.

  “Think of what that could mean for millions: the elderly who gravity has bound to wheelchairs; paraplegics and others who would benefit from low-gravity environments while recovering from illnesses … It would not be a high-stress three- to five-g ride atop a dangerous rocket; it would be the same as taking an elevator—a very long elevator ride of several days, the cab designed for comfort, almost like a cruise ship. Think of their lives when free of the bonds of earth.”

  She hesitated for a second; when she resumed speaking, there was emotion in her voice.

  “My grandfather,” she paused, “lost both legs and a hand at Stalingrad. He was a Stormovik pilot.”

  She paused again.

  “He flew nearly two hundred missions, most of them dangerous ground support, before he was shot down. Think of what living in low or zero gravity would have meant for him. He was the one who inspired me to go into this field of study.”

  That hit a nerve with Erich, a veteran of that war, and he nodded.

  “Convey my respect and honor to him,” he said softly. “We were on the same side in that war, and I see him as a true and gallant comrade.”

  “He died in a veterans’ hospital five years ago,” she whispered, voice filled with emotion, and Gary could see the subject was a sensitive one for her. “I would go with my grandmother every week to visit him. He used to say he looked forward to the day he would die and then could run again in heaven, and perhaps God would give him wings so he could fly again as well.”

  She lowered her head for a moment, eyes damp, obviously struggling to control her emotions. Gary was silent; Erich looked up at her, his gaze distant, as if remembering his own sorrows from that time.

  “I use to promise him that when I grew up,” she finally continued, voice a bit husky, “I’d find a way for him to run and fly again. A little girl’s promise. He’d hug me, laugh, I still remember the feel of his whiskers on my cheeks when he hugged me and how the nurses at the hospital treated him with such respect. He always wore his medals on his hospital bathrobe and…”

  She cleared her throat, coughing a bit nervously, her eyes bright with emotion, and then she looked back at the whiteboard, filled now with her diagrams and formulas.

  Neither of the men spoke, Erich just looking at her with a knowing smile, Gary averting his eyes and then noticing the framed Victoria Cross on the bookcase behind his mentor. Hero of the Soviet Union, Victoria Cross, both the equivalent to the Medal of Honor in America … He felt humbled.

  “It will make the rocket propulsion system obsolete,” she announced, swiftly but not too adroitly changing topics, “as obsolete as steam power for trains or piston engines for long-distance flight.”

  “In other words, your proposal would put a lot of people working at Kennedy Space Center and Houston out of business,” Erich said dryly, and Gary could see that the old man had been touched by her personal moment and was glad they had shifted back to this proposal. “I still do have a few friends working there.”

  She did not reply for a moment.

  “Should we have stuck with steam-powered trains, sir?” she finally replied.

  He chuckled and shook his head no, then looked over at Gary. It was time for the “gladiator games” to begin again.

  “Now, Mr. Morgan, I’ll give you the first shot at the questions.”

  Gary hesitated, still touched by the comment about her grandfather. His own grandfather had flown B-17s during the war, and he had gone to many an air show and several reunions as a boy. It had triggered his own fascination with aviation and that of his father as well. A father who had been a naval aviator, flown in the early days of the Vietnam War, then died in a senseless civilian aviation accident. No heroic medals—as was true for so many in that war and the one his grandfather had been in—for men who fought with utmost bravery, in conflicts where heroism was commonplace. Growing up, Gary and his father would go along with Granddad to air shows. The old man would always puff up with pride whenever he was near a B-17, and anyone within hearing distance, especially a fellow vet, would know he had flown one through twenty-five missions. On the other hand, there were at times long silences, and sometimes Gary heard him waking up in the middle of the night, crying out for a comrade to bail out, bail out …

  Gary wondered for a moment what had compelled Eva to go into aerospace engineering besides the memory of her grandfather. But then again, what had compelled him as well? Perhaps it really was the wonder of it all, the idea that a frontier still awaited.

  “Mr. Morgan, any comments, or are you so captivated by Miss Eva’s arguments that you fully agree and believe we should start construction tomorrow after I put in the hundred-billion-dollar budget proposal, which, of course, will pass without comment?”

  Gary looked over at her, made eye contact, and tried to smile, then saw that she was still a bit off-balance from a public recollection of what were obviously very private memories.

  “What are you proposing it be built out of?” Gary asked, going straight to the core problem.

  “We don’t have the material yet,” she answered openly, obviously having been hit by this question before, “but…”

  Erich chuckled as he tapped the ashes out of his pipe, refilled it, and lit it. Both looked at him.

  “We all know there is a ratio between compression strength, tensile strength, and width of the foundation. Cathedrals are a good example. As they strove for height, the width of the foundation had to become bigger. They solved it, at least to the limits of their ability, with the flying buttress support, but even then the practical limit for stone buildings was only several hundred feet before the foundation became cumbersome to the point of absurdity.

  “If you want an interesting example go, take a look at the highest stone tower in England, at Salisbury, at over four hundred feet high. The support beams inside the cathedral bulge outward more than a meter from the stress. A sharp eye by a full-time structural engineer assigned to that wonder, and high-tech lasers monitoring the bulges in the support columns, keep constant watch on it, because someday the stress overload will cause it to collapse. The same is true with any tower: the more weight compressing downward due to gravity, the wider the foundation. If we tried to build this tower with tungsten steel, for example, the foundation would be scores of miles in diameter, clearly an absurd proposition.

  “So, Mi
ss Eva, your answer?”

  She nodded in agreement.

  “Steel gave us the skyscraper,” Erich continued, “but above a few thousand meters, you start to run into the same problem, though you could just keep expanding the support base and make the building wider—but then, that adds more weight and more foundation.

  “You could build this tower of steel, even a Tower of Babel of bricks, but the foundation?”

  She smiled, sensing he was playing with her a bit, but Gary did know this point was true. You could build anything you wanted to any height if you kept broadening the foundation to bear the tremendous weight, but that, of course, did not take in a number of other factors that would tear a steel tower apart long before they even got a fraction of the height desired.

  “Even if you built it of diamonds,” Gary interjected, “I doubt if it would met all the stress demands.”

  “There’s promising research in carbon fibers,” she replied. “It is already revolutionizing aviation design, and the Japanese apparently are doing a lot of behind-the-scenes research on this.”

  Erich nodded.

  “To what percent of usability?” he asked.

  “I’m not sure, sir. That’s classified by them, and that fact alone should tell us they are onto something big. But the published literature is saying it’s moving along a lot further than anyone predicted five years ago.”

  Erich stood up and sighed as he stretched. For the first time Gary saw him walking and noticed a slight limp—a memento, he’d learn later, of a commando attempt to capture Rommel and the source of the Victoria Cross.

  The old man opened up his briefcase and, of all things, pulled out a pack of paper soda straws, then opened it up, drawing out several. Limping over to the whiteboard, he took the blue marker from Eva and drew three arrows alongside the line representing the tower.

  “Whatever it is built with has to be able to withstand three stresses. The first is compression, the weight of the object itself, which increases, of course, the higher up you go. You could actually build this tower out of soda straws, but at some point the weight of the straws above will cause the bottom ones to buckle unless you add more and more to the base until they cover half the planet.”