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What is Antimatter?
Envision a source of energy more than six thousand times as powerful as the current nuclear reactors, and that creates absolutely no pollution. Imagine a way to store enough energy in a small enough space to travel to another star system and back. Sound impossible? It's not. This source of energy is antimatter. Those of us who have watched Star Trek, or other sci-fi shows, have heard of antimatter. Many are under the false impression that it does not actually exist. In truth, it is not an imaginary substance invented by science fiction writers for use as a "magic" source of fuel. Antimatter is real, can be and is being made by humans, has fantastic potential for energy storage, and may be the most efficient form of fuel for future spaceships.
In order to explain the concept of antimatter in less than mind-boggling jargon, it is necessary to take a few liberties at the expense of true accuracy. Normal matter (the stuff that "has mass and takes up space," as most people define it) is composed of atoms which are, in turn, made of particles so small you can not see one by itself with even the most powerful microscope. Atoms are composed of a nucleus surrounded by a cloud of electrons (whose exact positions and velocities are not determinable). The nucleus contains protons and neutrons. Each subatomic particle (electron, proton, and neutron) has a spin and a magnetic field just as the Earth does. The protons and electrons also have an electrical charge. An electron's charge is exactly equal and opposite to that of a proton's. The electrons zip about in a cloud around the neutron/proton nucleus. Visualize each of the subatomic particles as being composed of wood fragments held together with glue, like particle-board.
Now, understand that antimatter is similar in construction to matter, insofar as it "has mass and takes up space." There are a few key differences. First, the charge on all particles is reversed. An anti-electron (or positron) has the charge of a proton. Similarly, an anti-proton has the charge of an electron. An anti-neutron still has no charge, since the neutron had none (negative zero is still zero). Second, the spin in relation to the magnetic field is reversed. All the little antimatter balls are spinning in the opposite direction from their normal-matter counterparts. Now, imagine that the antimatter subatomic particles are also held together by a glue, but this glue is made by a rival company. The anti-glue turns out to be a solvent for the normal-glue, and vice versa. When a piece of matter comes into contact with antimatter, the two glues dissolve each other. All the tiny pieces of wood are released. This "wood" is energy. Matter and antimatter are made up of energy somehow held together, and every last bit of that energy is released when matter and antimatter collide.
The description of antimatter above is, of course, partially theory. The existence of antimatter is not. Antimatter factories in both Switzerland and the United States churn out tidbits of antimatter daily. At CERN in Switzerland and at Fermilab in the USA, antimatter is created by smashing ultra-high velocity protons into copper or tungsten. Some of the fragments of energy resulting from the collisions form into anti-protons and anti-neutrons. Theoretically we should be able to make 500 anti-protons from 1000 normal protons however, the best we can do currently is 50 anti-protons out of 1000 normal protons. These antimatter particles are captured using magnetic fields and stored in antimatter "traps." The "traps" also use magnetic fields to keep the antimatter from straying from its home and getting into an energy releasing collision with normal matter.
Antimatter could conceivably be used as a highly transportable energy source for space ships (just as it is used in Star Trek). One gram of antimatter could power 47,564 hundred-watt light bulbs for one year. In other words, if one of my mother's size 9 tennis shoes was made of antimatter and was collided with the other one, it would produce enough energy to power the city of Anchorage for twelve and a half years.
In conclusion, antimatter is a highly compact way of storing energy, and if the efficiency of production could be improved from 5% to something more reasonable, we could begin manned exploration of our solar-system in earnest.
Additional Reference: The Chugach Outlet. October 1996. Published by Chugach Electric Association, Inc.
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