Moon dust danger could peak in 10 years

The same magnetic field that protects Earth from radiation could pose a hazard to astronauts on the Moon, a new study suggests. The magnetic field can dump electrons onto the Moon's surface, potentially damaging electronics and stirring up dangerous lunar dust.

The Moon spends most of its time well outside of Earth's magnetic field. But once each orbit it moves through Earth's long 'magnetic tail', which sweeps out behind the planet in the direction opposite the Sun.

Embedded in this tail is a region called the plasmasheet that is full of energetic electrons. When the Moon passes through this region, the electrons slam into the lunar surface and charge it with static electricity, a phenomenon observed by NASA's Lunar Prospector mission in 1998.

Static electricity could be a serious problem for lunar astronauts, because it can lead to 'sparks' – electric discharges that can damage electronics. It can also cause troublesome lunar dust to levitate above the surface, where it can more easily contaminate spacesuits and other equipment, possibly posing health risks (see Lint rollers may collect dangerous Moon dust).

Now, new research suggests this static electricity could be much worse for the next group of astronauts visiting the Moon than it was for the Apollo astronauts.

BUMP! The article linked goes on:

18-year cycle
This is because the amount of time the Moon spends in the plasmasheet, where it can mop up electrons, varies on an 18-year timescale. The variation is related to the tilt of the Moon's orbit, which can make the Moon pass above, below, or through the plasmasheet. "The total amount of exposure varies by a factor of two or three," says Mike Hapgood of the Rutherford Appleton Laboratory in the UK.
Static electricity would have been at a minimum during the Apollo missions, Hapgood says, but will be high at the time of NASA's planned return to the Moon in 2020. That is just past the maximum length of time the Moon spends in the plasmasheet, which occurs around 2016 to 2018.
"If you're thinking about going to the Moon and building a permanent presence there, then all these space environment issues are important," Hapgood told New Scientist. Sticky dustSandra Wagner, head of planetary environment management and integration at NASA's Johnson Space Center in Houston, Texas, US, says NASA is interested in how electrical charges affect lunar dust. "There are people who say that static electricity is going to be a big problem because the dust carries charge," she told New Scientist. "Others say the dust will stick to things because it carries a charge, but won't necessarily cause a big potential difference" in voltage that could damage electronics, she continues. "We're just trying to find out what is the reality as far as risk and then . . . we can start thinking about how to mitigate."
Hapgood says there may be ways to reduce any problems. Many airplanes, for example, have rods protruding from their wings to let static electricity leak away into the atmosphere, although this particular solution would not be ideal for use on the airless Moon.
Night risk
"There are technologies around for handling static electricity," Hapgood says. "We need to understand how to put these into the design of systems." Hapgood says one good thing is that the problem should be reduced during the lunar day, when astronauts are likely to be most active. That is because sunlight knocks electrons off the lunar surface, thereby reducing the charge. But astronauts may not be able to avoid going outside at night entirely, so the potential static electricity hazard should be investigated further, he says: "We need to quantify the risk and understand what it means."
Hapgood is presenting his research on the 18-year static electricity cycle at the Royal Astronomical Society's National Astronomy Meeting this week in Preston, UK.

Sounds like a serious engineering precaution is warranted. Doesn't sound like it should be costly...so long as dealt with "upfront". As Ben Franklin always said, the proverbial ounce of prevention, is worth a pound of cure...

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