Antimmatter Essay Research Paper Really long Physics — страница 3

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high melting point, but it is the limiting factor because of the high heat associated with this reaction. A more advanced engine concept composed of concentric rings of tungsten to enhance the heat transfer characteristics has also been looked into. This is the type of engine that NASA officials are considering for the manned missions to Mars. The mission would require about 400 metric tons of material which is 4.5 times less material then that which would be required for a conventional, chemically propelled system. Another engine plan would utilized a reaction chamber filled with high pressure gas into which the antiprotons are deposited. The changed annihilation products are trapped by the intense magnetic field, are slowed down, and heat the gas for expulsion. The advantage to

this engine is the ability to adjust the ratio of antimatter to matter. This allows the thrust to be adjusted according to conditions. Another even more possible use for antimatter propulsion combines fission. The main problem with antimatter engines such as the one previously describes is both size and feasibility. Several tons of antimatter would be required to complete such a job on antimatter alone. To add to that you need even more regular matter. Also, current production of antimatter is around micrograms, which puts the previous designs far into the future. However, do not rules antimatter out. Enter physicist Gerald Smith from Penn state. He has formulated an idea of combining antimatter with current technology. ?We?ll never have even a ton of antimatter, in my view,? he

says. ?We think we can ignite with a microgram of antimatter, which we can foresee doing with the current technology.? His proposition is to use antimatter to begin, and aid, a fusion reaction. His first objective was the problem of containment. After several successful attempts they doveloped a shoebox-size antimatter trap that could, in theory, hold up to 100 million antiprotons. Currently, researchers at the Marshall Space Flight Center in Huntsville, Alabama are building and even larger trap in hopes of such containment. This trap could possibly hold up to 10,000 times as many particles as the small trap. Tests have been planned combining this trap with a antimatter plasma gun which will be used to ignite the fusion reaction. Nuclear Fusion is very complicated, and would

probably require a whole other paper. It is present in nature and is the basis for most of the energy around us. Fusion requires large amounts of pressure and high temperatures. It is at the heart of the energy radiated by our stars. To give an idea of the temperature required for such a process; ?low? temperature fusion starts at 1.5 million degrees Celsius. This is where the antimatter fits in. The antimatter plasma gun is intended to create the high temperatures required for fusion. Fusion attempts so far, on earth, have been short lived. Fusion reactions have only been able to be sustained for a few seconds (without using antimatter). However, Gerald Smith (from Penn state) has been working on developing a engine that creates a self-sustaining fusion reaction triggered by

both an antimatter annihilation and a fission reaction. It starts with a small amount of antimatter, which is used to induce a fission reaction in lead or uranium. The energy released, in the form of heat and pressure, by this reaction is to help drive the fusion reaction using deuterium, or ?heavy? hydrogen, and a form of helium. This creates a plasma of negative electrons and positive nuclei of atoms. These particles shoot out of the magnetic nozzle, and are sent in the correct direction for efficient propulsion. The problem with this concept is the tremendous energy generated by the reactions. The nozzle would have to withstand huge forces of both heat and pressure. This problem has yet to be solved. Another problem is the size and weight of this device. One idea for reducing

the weight is dumping most of the hydrogen and instead building a huge collection scoop. This scoop would be the size of one third the distance to the moon, and magnetized so that it would separate hydrogen form the space dust. It would then condense it and use it as fuel. This scoop however would have to be far bigger then anything ever created on earth, and incredibly strong. All three of these methods are glimses into the future. They are, however, possibilities. The third system will probably be the one realized in my lifetime. In general, the antiproton powered engine may allow low mass-ration ships and fast transit-time missions to become possible. These two characteristics may not be simply enhancing but actually enabling to certain space missions such as interplanetary,