The Babylonians called it Nergal, associating the mysterious red planet in the night sky with the god of destruction and war; the Greeks attributed similar qualities to their god Ares and the Romans gave it its definitive name of Mars after their Lord of War. Mars has always fascinated humans and the ‘red planet’ has been a protagonist of mythology and literature until the modern era. The Irish writer Jonathan Swift was even astute enough to mention two ’minor satellites’ rotating around it in his famous account of “Gulliver’s Travels’, even as astronomers of his day had very few facts on the nature of this planet. Swift launched Mars as the ideal setting for science fiction adventures, a tradition highlighted by several books and films ranging from the works of Edgar Rice Borroughs to Ray Bradbury, Isaac Asimov and the more sarcastic Tim Burton, which depicts Martians as pure evil.
On August 6, the line between science fiction and reality grew fainter as NASA’s Curiosity rover landed on Mars on live television, a mission that has recaptured the collective imagination in space exploration as few others have done in recent memory. Curiosity represents the first complete mobile “science laboratory sent to a distant world”. The rover may discover evidence of organic compounds, suggesting the presence of life; it will also send unprecedented geological details about Mars. Ultimately, the ‘Curiosity’ mission holds the promise of an impending human mission to Mars, one that even the science fiction visionaries had not imagined, seeing as the Martians were typically the ones to visit us earthlings rather than the other way around. As imagination and science start to melt into one another, there is no fiction in the technology that has enabled NASA to land ‘Curiosity’ on Mars; and surely, its success will stimulate further exploration. In the post World War II period, solid fuel rocketry was seen as the main tool to explore outer space.
Today, as the distances that can be reached start to match our technological capability, rockets are no longer sufficient. Surely, rockets and boosters are needed to generate the power needed to break out of the atmosphere, but space travel to other planets is fueled by rare earth magnets, the very same at the heart of ion engines. Indeed, magnets based on samarium cobalt (SmCo) were first tested in October 1998 in NASA’s Deep Space 1. This was the first deep-space mission intended to illustrate the potential of new space exploration technologies. SmCo magnets are able to withstand high temperature operating environments, which makes them ideal for use in ion engines, the very same that will enable man to turn science fiction into science fact. Thanks to the use of rare earths, what was once merely hinted by Star Trek is within man’s reach. Ion engines will make manned space travel to Mars possible, reducing the time for the trip from the previously expected two years to less than three months. An ion engine uses a fuel source, such as mercury or – more recently – xenon or argon gas, which is then ionized and accelerated through a high temperature magnetic field. The atoms are ‘heated’ and expelled in the form of plasma. The temperatures reached in the heating process can reach a million degrees Celsius (the temperature of the core of the sun). Essentially, the magnetic field acts as a static component of the ‘engine’, which enables such mind boggling temperatures to be contained. The power generated is not huge in ‘earth’ terms; however, in space, in the absence of friction, a steady impulse of just a few dozen MW of power, and a few kilos of thrust, can gradually accumulate to create sufficient speed to reach Mars in a couple of months.
The power to ionize the ‘fuel’ comes directly from the sun. Ion propulsion makes a manned mission to mars far more possible and the technology is already available. NASA has awarded Electron Energy Corporation (EEC), the sole producer of rare earth magnets in North America, a Small Business Technology Transfer Research (STTR) contract to research and develop samarium cobalt (SmCo) high temperature permanent magnets for use in ion propulsion thrust engines. EEC has decades of experience in developing magnets able to operate at high temperatures having worked with the US Air Force and with other US military departments. EEC’s magnets have been tested in the ‘field’ thanks to a satellite, the aforementioned ‘Deep Space 1’, propelled by an ion thrust engine made by Hughes Electron Dynamics. Rare earths are essential components in the future of space exploration and the undeclared policy of allowing China to be the world’s largest producer of these essential elements is myopic at best. Ironically, rare earths can be found on the moon and on asteroids and if mining regulations in the United States are not eased, the very indispensability of REE’s may well be extracted from extraterrestrial sources. However, by that time, the US may well have lost its dominating place in space travel technology, using the same short-sightedness that allowed China to take over the production, and therefore the exercise of control over, essential technology. Excuses that REE mining is too environmentally damaging or expensive will soon prove costly; sustainable REE mining methods must be researched and developed in order to advance mining techniques.