Fusion
Thermonuclear fusion works by using a magnetic field to force plasma, consisting of certain species of hot, charged particles, within a vacuum chamber where they can collide and react. Since high energy particles can gradually work their way out of the confinement area, these reactors require a minimum size requirement. This aspect makes fusion reactors unattractive for today’s low power needs. However, in the future, our growing power needs will make this form of energy much more attractive and cost effective.
Fusion’s ability to provide massed amounts of power makes it an attractive source of energy for a spacecraft propulsion system. This would be a great form of propulsion due to the fact that the vacuum required can be had for free in any size needed. By far, the highest energy yield is the helium –3/ Deuterium reaction. However, the pure deuterium/deuterium reaction is 60% as good and much cheaper. A rocket engine based on controlled fusion could work simply by allowing the plasma to leak out of one end of a magnetic trap, adding ordinary hydrogen to the leaked plasma, and then directing the exhaust mixture away from the ship with a magnetic nozzle. The more hydrogen added, the higher the thrust, but the lower the exhaust velocity. The travel to Mars or our outer solar system would yield an exhaust of approximately 99% ordinary hydrogen. Rockets using yydrogen in their propulsion would have specific impulses of up to 10,000 seconds. However, rockets not using hydrogen could create impulses of up to 1.8 million seconds. The velocities created by such rockets could reach from 4 to 6 percent the speed of light. Unfortunately, the propulsion of such ships wouldn’t be adequate for in – solar – system travel. But, ships like those could make trips to nearby stars possible with trip times of under a century.
Fusion propulsion will make travel to Mars possible in weeks and to Saturn and Jupiter in just months. Also, trips to other galaxies would be probable in decades and not millennia. It is reasonable to think that fusion reactors would be used on a spacecraft first and not in stationary positions because the first steam engines were used for powering ships and the first efficient nuclear reactors were used on nuclear subs. Innovation has always been made in terms of power as an advancement to progress in a transportational and exploratory manner. Currently, the fusion field is progressing at a snail’s pace. This is the result of budget cuts due to shortsighted politicians who lack vision and senses of adventure. The Martian front may very well produce the exact necessity that is needed for us to start making breakthroughs in the field of fusion research and development. The Martian civilization may very well provide the basis for the survival of technological society.