100 years on
Magazine Within a Magazine. Celebrating 200 Years of Flight
- By the Editors
- Air & Space magazine, January 2004
Our imagined magazine, the issue that we think could appear in December 2103, referred to a space elevator and an interferometer stationed at a Lagrange point. Here are some of the preparations being made for technologies that will appear in another hundred years.
The L2 Lagrange Point
Eighteenth-century Italian-French mathematician Joseph-Louis Lagrange was the first to identify points in space where the gravitational tugs of two bodies are in balance. Any two bodies in mutual orbit, whether the Earth and Moon or the Earth and Sun, have five such locations (also called libration points) where a spacecraft won't be pulled into either body's orbit.
Since the 1960s, space mission designers have known about halo orbits -- small, tight circles around Lagrange points that allow a spacecraft to remain "parked" in interplanetary space with minimal fuel usage.
The Earth-Sun L2 point, located roughly one million miles from Earth in a direction away from the Sun, is the preferred destination for several planned NASA and European space telescopes. The Wilkinson Microwave Anisotropy Probe is already there, and more spacecraft will be stationed there in the next decade or two, including the James Webb Space Telescope and NASA's proposed Terrestrial Planet Finder. Many of these will be infrared telescopes, which work more effectively the farther they are from the warm, glowing Earth.
NASA also has been looking at L2 and other libration points as convenient staging points for human missions to the moon, Mars, and asteroids.
Astronomers have long known that combining the light from many telescopes effectively creates a single, giant telescope. This has been done on the ground with radio dishes like the Very Large Array in New Mexico. Eventually, astronomers want to build optical interferometers, made of many orbiting mirrors, that can "see" in ordinary visible light. A big step in developing the technology for these kinds of instruments will be NASA's Space Interferometry Mission scheduled for launch in 2009.
The Terrestrial Planet Finder, whose job will be to search for Earthlike planets, may be built as an interferometer, but it is undecided whether the elements will be attached to a common "boom" or will fly in formation, with their positions kept extremely stable.
Future space telescopes will have lighter mirrors that replace the heavy, old-fashioned glass in use today. Astronomers are now exploring these future telescope arrays at a conceptual level.
Once relegated to the world of science fiction, space elevators have gotten serious attention in recent years as a means to lower the cost of reaching space. A series of NASA and non-NASA conferences have concluded that the basic concept is feasible, although the engineering capability is not yet in hand. It could be in as little as 10 or 15 years, however, according to some experts.
The idea is to anchor a long-and extremely strong-cable at the equator, extending up past geosynchronous orbit, 22,000 miles above the Earth's surface. A "car" attached to the cable and propelled by a variety of means would move up and down. By the time it reached geosynchronous altitude, the car would be moving at orbital velocity (still anchored to the rotating Earth), and could be handed off into orbit. Or, from higher altitudes where it would have even more velocity, it could be slung out and away from Earth.
The biggest technical stumbling block has been developing a material strong enough to be used for the cable. Engineers believe they have found a solution in carbon nanotubes, a synthetic material far stronger than steel now produced in the laboratory. That breakthrough leads some Space Elevator gurus, like Bradley Edwards of the Institute for Scientific Research to predict that simple elevators can be built in the near future with investments amounting to several billion dollars.
Solar farm/hydrogen fuel depot
The hydrogen economy doesn't begin to take off until the early 2000s, when the four-wheel automotive industry begins serious development of fuel cells and other systems to escape the cycle of combustion of hydrocarbon fuels, in which ancient methane, petroleum, and coal are burned, releasing unwanted atmospheric byproducts. Hydrogen is initially derived from methane and ethanol generated through 20th century processes. The bio-engineering of existing species of plants that can survive-and even thrive-in irrigation with sea water opens up vast desert areas to the restoration of biomass, and in the short term, eliminates concern about shortages of traditional hydrocarbons while virtually doubling the absorption of atmospheric carbon dioxide.
Moving in parallel with these events are incremental, compounding improvements in the non-dynamic generation of solar energy from static, solar cells, initially, and later, from the combining of quantum solar generation as provided by the original solar arrays of the 1900s with the bio-engineering of bacteria that work in conjunction with the electrical cell to improve efficiency by a factor of three. The steady progress in traditional solar generation is the "tortoise" to the thermonuclear-fusion movement's "hare." (A popular 2102 hologram reads, "Fusion power is 25 years away, and it always will be," as an arch comment on the long-illusive technology of fusion.)
Dynamic solar energy from the heating of various media by large complexes of focusing mirrors and lenses driving some fluid from liquid to high-energy gases to turn a rotating power generator is under continuous development, but offers only minor improvements decade on decade. It is unable to keep up with the advances in static cellular arrays generating direct current to inverters, which convert it to standard AC. Lack of efficiency gains combined with high capital costs lead to the gradual abandonment of "steam" plants in favor of the cells, with the eventual biological breakthrough merely serving to seal the coffin.
So the production of plentiful methane and ethanol from biomass, coupled with massive investment in the process of harvesting hydrogen from these sources, provides an initial impetus to the conversion to hydrogen infrastructure. At Neil Armstrong Intercontinental Airport, the majority of hydrogen is produced through boosted electrolysis that relies on the bio-solar process. Recent introductions of proprietary bacterial strains from a Brazil research laboratory have bumped up efficiency another 2.2 percent.
The result of a whole century of development and energy evolution is plentiful energy for the foreseeable future but at significant cost to users as the enormous capital investment in infrastructure cannot be recovered until 2140 at the earliest. And who knows what new investments may yet be needed?
The merging of the so-called "hard" and "soft" materials into bio-alloys that mix traditional metal alloys in matrix form with chemically and molecularly versatile elements such as carbon, silicon, and lithium in combination with synthetic cellular elements that mimic mitochondria, vacuoles, and microtubules in their interaction with the medium surrounding them has literally recast material sciences and altered design and manufacturing. By managing the properties of these alloys as well as distributing actuation at a molecular level, the old mechanical picture of everything from vehicles to building construction has become no more than a fond memory.
Two-century-old works of fiction that describe morphing vehicles do not get it all quite right, which is not so surprising considering the abrupt changes in direction the technology has taken.
Offshore international airports
To remove the noise of hypersonic aircraft from the settled areas of the mainland, nodes for hypersonic travel begin in 2040 to be located offshore near the major markets they serve. The first of these are built about 45 miles off the California coast of the United States and some 150 miles southeast of Okinawa-Japan doesn't want to hear the faintest rumbling of thrusters-and connected via high-speed magnetic levitation trains and aircraft to terminals on the mainland. This same model was repeated across the globe as former land-based international terminals for flagships of the fleet became secondary airports acting as distribution points for passengers and freight to inter-urban areas, and eventually to the metro-rurals as the population dispersed.
Older spanloaders mix somewhat awkwardly with the scampering hyperliners, but their low-cost inter-airport services are crucial to knitting the entire global system together. Nearly inaudible and completely automatic, the slower "spans" pioneers the pilotless massive-database systems that now also operates personal fliers.
Catapults are introduced in the second-generation airport designs and during renovation of the first generation in order to minimize the required installed thrust aboard hypersonic liners. Requirements for takeoff thrust acceleration create a weight penalty for the precisely designed hyper-liners, which are extremely sensitive to each gram of structural mass in terms of economic return. By offloading propulsion and fuel weight to the catapult, the designers of hypersonic airliners see the new technology come into its own.
At roughly the same time, the International Aerospace Development Organization devises a new configuration for travel in which passengers and the vehicles that carry them are forever spared the necessity to match up on sprawling airport gate complexes designed to accommodate the outside dimensions of immense aircraft. Replacing the outmoded model is the current pod-based scheme in which passengers board containers that mate with airframes at a docking facility. Electrical, signal, and environmental connections are made automatically as the two are mated. Pods are self-contained escape and rescue elements in the event of catastrophic airframe mechanical failure. Ballistic parachutes lower the pods to the ground or to a water landing, where the pods can remain afloat indefinitely until rescue can be effected. Synthetic vision forms an uninterrupted lining along the walls and overhead of the interior of each pod and provides a passenger selectable image that can follow each person's visual cone if they choose to move about the cabin at cruise; most travelers don't choose to, preferring to absorb information on the region they'll be visiting by means of multimedia "fountains," a term that describes the high rate of transfer and intensity of experience.
The Neil A. Armstrong Intercontinental Airport, located well west of San Diego, takes the traditional offshore architecture to a whole new level, recognizing the fact that these airports have increasingly become destinations in their own right. Their enormous, durable structure provides a natural site for a wide variety of service industries unrelated to the international air travel that was their original purpose. Hotels, free trade zone giga-malls, communication and entertainment headquarters, and marine adventure services, to cite just a few examples, abound at Armstrong and others now on the drawing boards. Travelers and visitors to Armstrong enjoy many levels of underwater viewing spaces, shops, theaters, and arcades. When the Google Network broadcasts its Millennium Holiday Special in 2100 from the Leroy Chiao International Airport serving the island complex of the International Space Elevator, with hologram repeaters projecting the show in the skies over every major city of population two million or more, the company makes ratings history with a 97 share.
The rebounding of biomass that gathered speed after 2025 altered so many historic assumptions about transportation, energy management, and the global environment that government and industry were able to draw up a future scenario from a clean sheet of paper. The drive toward dramatic increases in fuel efficiency for surface transport-wheeled vehicles-yields to new calculations that assume the elimination of all paved surfaces needed to support wheels and the benefits that accrue if transportation becomes almost entirely airborne. Managed by a series of massive information nodes located approximately equidistant around the globe, the global airspace system represents the unlocking of personal, commercial, and industrial transport from centuries of surface-bound limitations.
The fliers are never sold but instead leased to users so that the manufacturer retains perpetual control of the vehicles in order to track them , recall them if necessary, and eventually to scrap them when their time is up. There are no antique fliers for collectors to restore, but on the other hand, there are no ancient-and dangerous-clunkers plying the airways either.
The creation of rugged, durable composite materials with some qualities of living tissue provides the basis for extremely lightweight designs that change shape in complex ways to alter their own aerodynamics as well as their physical configuration. Ducts and exhaust outlets appear and disappear. Stub wings extend, retract, and change shape to meet command requirements from the vehicle management system, which is made up of microelectronics embedded throughout the material. Thump it with your fingers and the material resounds like wood, but apply the tiniest electrical signal in the form of packets of code and it responds as adroitly as a big muscle.
The propulsor, with an advanced ceramic composite core, provides lift and forward thrust through variable ducts that morph on command. Endurance of about an hour and a half between fuelings is sufficient for almost any typical trip.
A parachute recovery system canopy is embedded within the outermost layer of the craft's upper surface at the time of manufacture. While this part of the system is a permanent part of the craft throughout its service life of roughly 20 years, the command module and activators are test and replaced about once every five years or so, depending upon local conditions.
Roads, highways, the interstate system-all infrastructure related to the wheeled culture of the automobile-is gradually removed and replaced with either greenspace or buildings. As paved surface withers across the landscape, groundwater and major aquifiers are replenished by the improved percolation of rain water.