By 
September 1st, 2020
Apollo 17 helmets and dusty spacesuits stuffed inside lunar lander following the last human treks on the Moon in December 1972.
Credit: NASA
Between 1969 and the end of 1972, twelve U.S. astronauts kicked up the powdery regolith, the topside dust and rock of the Moon. They were later dubbed the “dusty dozen.” Along with invaluable lunar samples, Apollo moonwalkers brought back a significant message to Earth: The Moon is a Disneyland of dust.
A team led by the University of Colorado Boulder has come up with a potential solution to the problem: one that makes use of an electron beam, a device that shoots out a focused stream of negatively-charged, low-energy particles.
Dust up on the Moon. Apollo 17 commander Eugene Cernan prepares to doff lunar dust-covered space suit.
Credit: NASA
The research group’s early findings suggest that electron-beam dustbusters could be a fixture of Moon bases in the not-too-distant future.
The research has been published recently in the journal Acta Astronautica.
Dust hazards
“Dust mobilized on the lunar surface due to natural processes and/or human activities can readily stick to spacesuits, optical devices, and mechanical components, for example. This may lead to dust hazards that have been considered as one of the technical challenges for future lunar exploration,” they write.
Furthermore, lunar dust poses a health hazard to Moon crews. Apollo 17 lunar module pilot Harrison Schmitt’s exposure resulted in symptoms he described as “lunar hay fever.”
A vacuum chamber on the CU Boulder campus.
Credit: IMPACT lab
The research team’s new method utilizes an electron beam to charge fine-sized dust particles and shed them off of various surfaces as a result of electrostatic forces.
Jagged and abrasive
To test the idea, a vacuum chamber was loaded with various materials coated in a NASA-made “lunar simulant” designed to mimic lunar dust. After aiming an electron beam at those particles, the dust poured off, usually in just a few minutes.
In their paper, the team reports that an alternative dust removal method using a short wavelength UV light will be also tested in future work.
A vial of Apollo 11 Moon dust from a lunar sample collected in 1969.
Credit: Marilee Bailey/Lawrence Berkeley National Laboratory
“Lunar dust is very jagged and abrasive, like broken shards of glass,” said Xu Wang, a research associate in the Laboratory for Atmospheric and Space Physics (LASP) at CU Boulder. The problem with lunar dust, he adds, it isn’t anything like the stuff that builds up on bookshelves on Earth.
Moon dust is constantly bathed in radiation from the Sun, a bombardment that gives the material an electric charge. That charge, in turn, makes the dust extra sticky, almost like a sock that’s just come out of the drier. It also has a distinct structure, Wang noted in a CU Boulder press statement.
By using the new technique, “It literally jumps off,” said lead author Benjamin Farr, who completed the work as an undergraduate student in physics at CU Boulder.
Flow chart shows the possible health effects of breathing lunar dust, in both the short- and long-term.
Credit: Rachel Caston
Electron beam shower
Study coauthor Mihály Horányi, a professor in LASP and the Department of Physics at CU Boulder, believes the technology has real potential.
NASA has experimented with other strategies for shedding lunar dust, such as by embedding networks of electrodes into spacesuits. An electron beam, however, might be a lot cheaper and easier to roll out, Horányi explains.
Moon base design.
Credit: ESA/P. Carril
Horányi imagines that one day, lunar astronauts could simply leave their spacesuits hanging up in a special room, or even outside their habitats, and clean them after spending a long day kicking up dust outside. The electrons would do the rest. “You could just walk into an electron beam shower to remove fine dust,” he notes.
Credit: NASA
Other coauthors on the new research include John Goree of the University of Iowa and Inseob Hahn and Ulf Israelsson of the Jet Propulsion Laboratory.
To read the paper – “Dust mitigation technology for lunar exploration utilizing an electron beam” – go to:
https://www.sciencedirect.com/science/article/abs/pii/S0094576520304902?via%3Dihub
Also, go to this video of jumping motes of Moon dust at:
Posted in Space News
