There is no liquid water on the Moon, and this is a more serious problem than you can imagine. No, I'm not talking about astronauts' thirst (we have solutions for that), but something infinitely more insidious: the moon dust.
Without the erosive action of water that smooths out every edge on Earth, the grains of lunar dust are like shards of glass and electrostatically charged, turning them into tiny, sticky demons that cling to suits, lenses, gaskets, and equipment. A curse on any prolonged mission.
The same moondust that turned Apollo heroes into space chimney sweepers could now be kept at bay thanks to a surprisingly elegant solution: an electric force field that NASA just tested successfully.
A problem as sharp as a razor
Moon dust is not like the dust you find on your furniture. It is the result of billions of years of micrometeor impacts on the lunar surface. In the absence of water and erosion, each individual particle retains razor-sharp edges. As if that were not enough, the constant bombardment of cosmic rays has given each particle an electrostatic charge.
The result? A carbon-like dust that sticks to everything: spacesuits, lenses, gaskets, and other equipment. This has been a problem since the first lunar landings in the 60s, when Apollo astronauts would return to the Lunar Module looking like coal miners, with dust getting everywhere, interfering with equipment, wearing out components, and doing Armstrong and his colleagues no good for their lungs.
Moon dust, a bit of applied physics
To combat this microscopic enemy, NASA has developed theEDS (Electrodynamic Dust Shield), which uses a pattern of tiny electrodes that carry a high voltage AC signal in the kilowatt range in a phased sequence. This alternating electric field produces what are called dielectrophoretic forces: essentially a non-uniform electric field that creates a traveling wave that can push lunar dust across the surface.
By adjusting the phase pattern sequence, the powder can be moved in the desired direction, sweeping it away as if an invisible hand was picking it up. I like to think of this technology as a kind of electric broom without bristles, which simply tells particles: “Move, please.”
A field test (of strength)
The system was transported to the Moon aboard the Blue Ghost Mission 1 mission. Firefly Aerospace, whose mission ended on March 16. The gif animations released by NASA clearly show the effectiveness of the system: the “before” image shows the dusty test area, while the “after” image reveals the work done by the EDS.
The end result is a system with no moving parts that can continuously or periodically remove lunar dust from optics, solar panels, spacesuits, visors, radiators, windows and other surfaces without wear. While not yet a system ready for deployment, the latest experiment demonstrates the potential to protect future missions from this plague.
We always think of the big obstacles in space exploration as the most obvious and dramatic; instead, it is often the microscopic details that pose the most insidious challenges. In this case, the solution is as elegant as the problem is annoying: an invisible wave of force that sweeps away what would otherwise be an insurmountable obstacle to our permanence on our natural satellite.
