§ 5.13: PERMANENT and Biotechnology
It is well established that zero gravity enables or makes much easier the sensitive processes for separating biological molecules. Many of the biological payloads flown into space and returned to Earth were for this purpose. Zero gravity prevents settling so that more sensitive forces can operate. Also, zero gravity prevents convection currents which stir materials.
The most common separation process is electrophoresis, also usable in outer space for nonbiological applications as well. Many biotechnology electrophoresis experiments and production processes have been performed and continue to be performed on the US Space Shuttle.
Other benefits are safety and sample contamination issues. A facility in space is isolated from Earth and thus there are fewer ways that experiments and production can be contaminated. In the other direction, dangerous substances probably cannot enter the Earth's biosphere.
The latter issue is becoming increasingly vital. As biotechnology advances and we become more capable of treating human diseases, we also become more capable of creating a substance that could escape the laboratory and inflict heavy casualties among the general population. For example, what would happen if experiments using the AIDS virus accidentally produced a strain that spread as easily and quickly as the common cold? There will come a time when potentially dangerous biotechnology experiments should be banned from Earth and moved into outer space.
The main economic benefit of using asteroidal and lunar materials is making the facility to be used for biotechnology experiments and production -- the structure and fitouts, the power plant, the radiation shielding, and the orbit maintenance fuel. The biological materials would be launched up from Earth (except, perhaps, if they're plant-derived, and then we can use asteroidal or lunar dirt for growing them).
Another substantial economic benefit is that the material can be returned to Earth without spending any money launching a vehicle up to rendezvous with the space station. Simple re-entry vehicles can be made from nonterrestrial materials, e.g., sintered asteroidal or lunar minerals, or manufactured ceramics, and sent on their way using asteroidal fuels. Alternatively, the material can be braked to zero velocity in orbit using asteroidal fuels or, if they're strong materials, an electromagnetic launcher can perform this role using only electricity. By the zero velocity route, we avoid more than 90% of the heat of re-entry. Indeed, with cheap enough fuel from asteroids, we could soft-land or parachute ballistic payloads using recycled rocket engines used to boost satellites into orbit. Just retrieve them, refuel them, and send them the other way.