Space Exploration Technology
As space exploration technology advances and men and women stay and work in space for longer durations, some interesting products for production in space will be developed.
Space has possibilities for industry that are not possible on earth. Technologies using zero gravity and zero atmosphere have special applications in medicine, metallugy, and general research. Space is the ideal laboratory for many types of reseach and for some industries, space offers some exciting potential.
For many drugs the only way of getting them is pure form is through the use of separation by capillary action. This process is limited on earth by gravity, making it extremely expensive to get sufficient quantities of drugs which are processed in this manner. Many anti-viral and anti-cancer drugs are processed in this manner. Test made during shuttle flights have shown that yeilds of drugs produced in this way are higher in the zero gravity environment of space. Test have also shown that certain diseases are slowed in low gravity environments.
Gravity is the enemy of one of the basic elements needed for making alloys, diffusion. To explain; alloys are mixtures of two or more elements into a unique metal. Bronze (copper and tin) and Brass (copper and zinc)are example of alloys. Steel is a group of alloys of iron and other metals. The problem is consistent mixtures between lighter and heavier metals is often defeated by gravity. Gravity causes metals to settle settle or separate stopping the complete diffusion or mixing of the molecules of the metals. Alloys made up of lighter and heavier metal are often not practical or cost effective because of this gravitation separation. In the zero gravity environment of space this is no longer a problem.
Metals can be mixed and formed in a zero gravity environment without concern because they would act as fluids. This means they would diffuse much the same as ink does in water, spreading thoughout until a uniform consistency is achieved. In a zero gravity environment exotic mixtures of metals into alloys not possible on earth could be achieved.
Another use for space in the area of metals would be in the production of "foam" metals. In space liquid metals like steel could be "foam formed". Gases could be bubbled through metals while being extruded or molded, producing metal parts which are much less dense yet generally as strong or stronger than their "solid" counterparts. For instance, a grider made of "foam" steel could be made "lighter" less dense than aluminium, yet have the characteristics of steel.
Space makes "foam" metals possible because without gravity gases would diffuse more evenly and completely and not be squeezed out or collapsed by the weight of the metal.
The concept of growing plants in space for long range space voyages has been looked at as a necessity by many who plan for future trips in space. Plants provide the only logical way to recycle air and liquid and solid waste. Since they take in carbon dioxide and water, and give off oxygen and produce food using photosynthesis, it is clear that they would have to be included on any voyage in space. However the effect of zero gravity and the possibilities of the use of controls to generate optimum yeilds has lead to proposal by some to experiment with "space farms".
Because the environment in any enclosure would be controlled, farms in space would be able to optimize conditions like amount and wavelength of sunlight, optimum fertilizering, temperature, and just about any other factor including gravity. Because of the weigthless conditions in space, such farms could be "soiless" using hydroponics to provide water and nutrients. These farms could also be set to grow in three dimensions since gravity would not be a factor. At the same time this lack of gravity is also an unknown factor. How would plant grow without gravity to direct their roots and leaves? Yet it is also possible to make changes in gravity in a space environment. And gravity and its effects are not the only unknowns.
There are so many factors that are not known in growing living things in space that the range of possible experiments to answer questions on growing plants and animals in space is endless. Everything from growing plants and herbs in varying environments to optimize products or yeilds; to experimenting to develop new types of foods grown in the unique environment of space is possible.
Space is in many ways the ideal laboratory. No gravity and no air produce a unique environment for several experiments, tests, and industries. Think of something as simple as a light bulb, they could be manufactured in space without the need of vacuum pumps. Dusk free clean rooms, hard vaccums, controlled gravity are all examples of things that are difficult or impossible on earth that are relatively simple in space and are part of the natural environment there.
Space lends itself to industries where air and gravity are problems. Things like low temperature welding, thin molecular coating (coating a surface with a layer that is only a few molecules thick), crystal growing for semi-conductors are just a few examples of industrial processes that better suited for space.
In the 1970's few people understood the possibilities that could become realities as a result of space research. Many of today's technologies are a result of man's first explorations into space. Today as space becomes a place where people work more and more, it is clear that industries will be developed around that fact. The PC and satellite television are offshoots of the first generation of space exploration, it is hard to guess what will be the result of men and women living and working permenantly in space. The one thing that is sure is that there will be new industry based on the unique environment of space.
There are organizations like the L-5 society who have proposals for working, experimenting, and even living permanently in space. When men and women do start to work permenantly in space, who can say what new industries, products, or services might develop? We had no idea that putting men on the moon would lead to the communications revolution. Where might the establishment of a space station lead? If past experience is any indication, we are in for another technological explosion.