Number: 747 Name: HWY TO EARTH GEO RING
Address: J.E.D.CLINE1 Date: 890209
Approximate # of bytes: 15120
Number of Accesses: 17 Library: 3
General audience writeup of the kinetic-energy-supported space elevator structure concept, providing economical transportation into space at high payload volume, primary power from SSPS, including surplus power delivered to earth; spacecraft construction at GEO, Stanford Torus type space habitat construction at GEO.
HIGHWAYS TO THE EARTH GEO RING
J. E. D. Cline
Fortunately, the resources of energy to make things happen, raw materials for building things, and vast room to live in, so needed now to take the burden of mankind's greatness off of the ecosystem of our Mother Earth, is available in space. Those resources are close, starting only ninety miles or so away, 90 miles straight up overhead, that is.
Although that ninety miles is a steep climb, one whichthe world is currently able to make for only a few people ata time (without much of a place to go, either; no hotels there yet) aboard chemically fueled spacecraft like thespace shuttle, the key links for creating a true highway forthe bulk of humanity into space may already exist in concept. Let me show you a neat design for connecting thoselinks into a unified picture of Earth's ecological system, human civilization and highways to space habitats.
First we need a hypothetical belief that it can be done, can be achieved, and done well. That belief will lift us up out of appearant dead-end tracks along the way, energizing us with a reminder of the whole picture, the map.Yes, we CAN get there from here.
Next, a quick reminder of why we need to do it. Like humanity eliminating forever one species of earth life forms every week or so, mostly in the rainforests being slashed and burned for farm land, then exhaused to waste land. Add to the list that the arid waste lands of the entire world are collectively expanding at the rate of about 40 square miles per day. The Sahara desert once was a well-watered savannah. We are burning up many billions of dollars of fossil fuel petrochemicals every year, and replacing none of it. Worldwide we pile up one billion tons of garbage per year, putting it somewhere. OK, that is enough thinking about this; let's not get down in the dumps with fascination about such things. Solutions are at hand, harmonious solutions. Believe.
Looking upward and outward for a new place to live for teeming humanity, let's creatively explore how to get there and where to live exactly, once there.
Chemically-fueled rocket propulsion transportation seems much too limited in this application, due to the enormous chemical energy needed to conventionally lift into space, per person. There are several billions of us needing to go, and soon, if we are to stop crushing our beloved planetary ecosystem. Most of the energy in chemical rocketry is used just to lift the fuel itself; relatively little of that fuel energy is used to lift payload itself. So let's look at the past for solutions, in light of today's technological advances.
Eliminating the fuel used just to lift most of thefuel, would make the process far more efficient. If thevehicle is already moving fast enough, say 18,000 mph, as itleaves earth surface, that would put it into orbit withoutlifting fuel just to lift fuel...if our atmosphere were notin the path, that is. Trying to punch its way through theair at 18,000 mph would consume its velocity and destroy itwith the heat caused by shoving that much air aside thatfast. Like a meteor burning up. So...let's move the airaside first, out of the path. Move the vehicle through atube which has had all the air pumped out of it, ahead oftime.
A very long tube it would be, and surely very heavyaltogether. How to hold it up? By converting our 18,000mph vehicle into a steady stream of vehicles, each of whichdrags upward a little on the tube as it rises toward space,the tube can be supported in the earth's gravity field.Shifting our thinking a little more, convert the vehiclesinto just a mass stream moving at the 18,000 mph within thevacuum inside of the tube, the mass stream supports the tubeby giving up a small part of its velocity, its kineticenergy, as it flows through the tube. The tube then becomesa fixed structure, attached to the earth's surface on oneend. This structure could be used to move vehicles alongits outer surface, like an elevator does. A "spaceelevator".
The elevator cars on such an elevator could lift upwardby electromagnetically dragging against the upward streamof mass within the tube. Low friction tracks, such asmagnetic levitation tracks, would make the process moreefficient. No fuel for this process is needed to be lifted.
The mass stream in the tube travels in a circuit,returning back and forth between earth surface and somewherein space. Ideas are built on ideas; a version proposed byKeith Lofstrom would cycle from one point on earth surfaceupward, across some great distance, then return to surface,be reversed, go back along the route to the starting point,all in a continual flow. Expanding on this, Earle Smithproposed a continuous flow from one point on the earth,circling out to geophysical earth orbit (GEO), continuing onaround the earth to return to the intiial point on theearth, again in a continuous stream. Rod Hyde proposed aversion that would essentially go straight up; the streamwould be reversed in direction at its upward end, returningdown alongside the upward part of the stream, back to thestarting point on earth, back and forth between earth andspace.
All these versions are powered by electricity. The massstream is pushed along by magnetic fields interactingbetween the stream and magnetic fields alongside the tube.Rod Hyde envisioned the stream as being composed by vastquantities of berylium disks, each with a magnet attached.The stream would be powered by electricity, and a largeversion consuming as much electricity as a large city, wouldbe able to lift all the billions of humans on the planetnow, out into space in just two weeks' operating time. Hyde,Lofstrom and Smith presented these concepts in 1984. Theirstructures are very big and expensive, and untried. Puttingsuch structures up seems a major undertaking with muchrisk, even worldwide. However, these structures have thepotential of being able to move the bulk of humanity outinto space. If they had somewhere to go, that is. It wouldtake a lot of courage to put such structures up, it seems.
Getting back into the creative thought mode, let'scontinue on with the design. Where do the people go, inspace? Well, there are limits to where these elevators cango, for they are essentially compression structures,depending on compressive force to hold them together. Thus,they would not be able to go beyond the geophysical orbit;in fact, Hyde's version depends upon earth gravity toreverse the flow back toward earth surface at its upwardend, thus not able to reach GEO by itself. And anythinggetting off these elevators short of GEO would fall back toearth, fast, unless accellerated adequately first, as inLofstrom's Launch Loop versions. GEO, geosynchronous earthorbit, seems ideally suited for the upward terminal of suchelevators, because GEO is stationary relative to theearth's surface. Thus one end of the elevator is on theearth, motionless; the upward end is stationary at GEO.Anywhere else would require relative orbital motion; theconnection between elevator and upward orbital terminal thenwould become high-velocity, requiring complex energyexchanges as payload moves between them. At GEO, payloaddirectly connects to the orbital terminal. Hyde's versionof the space elevator might use a long tether balancedacross GEO, the tether's downward end reaching the top ofthe elevator, so as to span the remaining distance to GEO.
Here at GEO we can build space colonies, space habitatsor settlements. If we build the wheel-shaped Island OneStanford Torus space settlement design envisioned by NASA in1975 (ref. NASA SP-413,although for use at L-5 then), thereis room for 1,475,000 of these wheels, if strung togetherlike pearls on a necklace for mother earth, circling theearth above the equator, 5 earth radii above the planet'ssurface. In the Stanford Torus design, the wheel is over amile in diameter, rotating so as to provide earth normalartificial gravity effects, and the wheel innertube is 427feet wide inside. Divided up into three secions ofagriculture, alternated with 3 sections for human residenceand light industry in closed ecosystems, this single ring ofStanford Torus wheel-like habitats around the earth wouldhouse up to 15 billion people, far more than the whole earthhas now or possibly could accommodate well. Solar energyabounds up there, on the average seven times as much asarrives on an equal surface on the earth. Sunshine abundantfor growing crops in the agricultural areas on the StanfordTorii, which in turn feed livestock and the humanpopulation.
It would be well for there to be many such elevatorsconnecting earth to this GEO habitat ring, perhaps eachnation would have at least one elevator. The initialStanford Torii would be built from materials lifted up fromthe earth, along with the robotic machinery to continuallybuild more of these habits.
Once there are these space settlements up there, a fewat least, with 10,000 people each, the picture of space willlook different. Building spacecraft up there, it will berelatively easy to return to the moon, from where we willget most of the structural raw materials for most of theStanford Torus habitats to be built in GEO. Trips out toget asteroids for more material would become as commonplaceas airplanes now land and takeoff at airports. Water andother valuable chemicals might come from the moons of theouter planets, if we choose not to take the water from earthglaciers instead, to water the agricultural areas in thespace habitats.
Electrical power to run the space habitats comes fromsolar power stations, designed in the '60's. The sametechnology might well be used alongside each of the spaceelevator structures, supplying power to operate theelevators, instead of using energy from earth. Indeed, thesolar power satellites could put extra energy intoaccellerating the elevator mass streams in the downwarddirection, which could be drawn off from the stream'skinetic energy at the earth surface contact sites, to supplyelectrical power to power whatever human civilizationremains on the planetary surface. However, hopefullyhumanity will be responsible enough to have people only onearth surface to restore the planetary ecology, and runvacation resorts for GEO ring residents.
This overall design of kinetically-supported spaceelevators linking a ring of space habitats located at GEO,all powered by solar power station technology, and withtransportation materials link from the ring to the moon andelsewhere in space, seems cohesive. Thus it is due furtherdesign work. To deveop technology and get real-worldexperience with the dynamics of long space elevator-likestructures, perhaps the concepts could be reduced toessences. For example, the mass stream perhaps could beglass fibers, with magnetic material embedded within thefiber at specific distances along it. These fibers could beelectromagnetically accellerated within a fine tube, say 20mils in diameter. The tube would be pumped free of air, andthe fibers prevented from contact with the tube walls viaelectromagnetic fields along the tube. With a reflector ofthe steam of fibers at one end, the reflection processresults in a tensile force; this force could provide liftenergy for the end of the tube. As in the larger versions,some of the kinetic energy of the rising high-velocity massstream of glass fibers would be used to support the tubealong its length. Steering of the rising end could beaccomplished by shifting the center-of-gravity of thereflector relative to the tube, providing off-balancelateral forces, resulting in a steering mechanism. Thestream would be accellerated on the earth surface; coiledprior to raising, the volume of this example would be onlybe equivalent to a cube 50 feet on an edge, and the lengthstill be able to reach almost to GEO. A longer versioncould emplace a seed elevator of the kind that loops fromearth surface, out around to GEO at the opposide side of theearth, continuing to loop back to the starting site onearth surface. Bundles of such micro-diameter spaceelevators might be used to support very large elevator carsgoing to GEO, carrying materials, tools, and personnel tobuild the first space habitats there.
This design for an expanding human civilization locatedin near-earth (GEO) space, linked directly to the earthsurface by kinetically-supported space elevator structures, powered by solar satellite power technology, and a healing of the earth's ecological system, would require only technology development, not major breakthroughs in science.The untested basic concepts of elevator transportation into space need to be demonstrated to the public eye, as well as catching the public awareness for presentation of such opportunities to take the ecological load off of mother earth while at the same time provide for a greatly expanding human civilization. Given the viability of this scenario, the implementation of it would remain the decision of a responsible humanity. If undertaken as a major effort (say, using half of what each nation now spends on defense preparations each year), this would become one of the great adventures of all time for the majority of humans now living on earth surface.
References: GEnie Spaceport Library, files # 690, 671, 655, 644, 634, 629, 592, 581, 573, 563, 553, and 475.
by James Edward David Cline ("Jed")
Van Nuys, California February 9, 1989