During the Apollo Program, astronauts on the Moon encountered a small menace that created big problems: lunar dust. Similar to how tiny bits of Styrofoam behave on Earth—adhering to anything they touch—lunar dust sticks to spacesuits, spacecraft, tools, and equipment, and is extremely difficult to remove. The clingy nature of the substance is partly due to its electrostatic charge but is also due to its physical characteristics: The sharp, irregularly shaped grains have edges like burrs and feel like abrasive talcum powder to the touch.
Not only a nuisance, Moon dust is also a potential health and safety risk. Because it is often laden with ultraviolet radiation and high iron content, it can be detrimental if it gets into the eyes or lungs. In fact, some of the particles are so small that the human body does not even detect them in order to expel them. On the Apollo missions, equipment covered with the dark-colored Moon dust suffered from the absorption of sunlight and tended to overheat.
NASA has investigated tools and techniques to manage the sticky stuff, including magnets, vacuums, and shields. In 2009, Kennedy Space Center collaborated with a small business to investigate a method to harden the Moon’s surface—in a sense, to “pave” the surface—so astronauts and robots could land, drive, and work without disrupting and scattering the material.
Kennedy awarded Small Business Innovation Research (SBIR) funding to Troy, New York-based Ceralink Inc., a leader in the development of microwave processing technologies, to demonstrate a microwave system that could heat lunar soil to over 2,000 ˚F, temperatures high enough to solidify the surface. The company performed demonstrations using microwave technology, which could be incorporated into a roving lunar system, to heat the surface of a large bed of 8-inch deep simulated lunar soil.
“When you heat the dust, it densifies or melts, becoming glassy and hard,” says Holly Shulman, president and CTO of Ceralink. “The technology could potentially be used to make miles of road on the Moon.”
The technique employed through the SBIR applied microwave heat only to the surface of a material rather than an entire object. In addition to demonstrating this new approach, Ceralink also examined the feasibility of using computer modeling software to simulate microwave heating on a larger scale.
As part of the SBIR, Ceralink teamed with Rensselaer Polytechnic Institute (RPI) and Gerling Applied Engineering to investigate and refine the computer modeling technology. This opportunity allowed the team to test the modeling program against an experiment. “By the end of the project, the model was at the point where it was matching up very well with what we were doing in the lab,” says Shawn Allan, Ceralink’s principal investigator on the project. “We had experiments and also a computer model that was backing up our experiments.”
As a result, the team advanced a computer modeling capability that is now incorporated into Ceralink’s commercial services.
Ceralink specializes in microwaves, materials, processing, and design, providing microwave technology for research and manufacturing of ceramic materials, glass, metals, and polymers. The company’s microwave testing center boasts a range of heating equipment for a variety of processes, and when customers are interested in exploring microwave heating, Ceralink performs the tests in its lab. “The customer might be interested in energy savings, or running their process faster, or looking to see if they can get better properties by using microwave,” says Allan.