First pictures of Martian dust: It’s 1 micrometer in diameter, and it’s dangerous

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It’s a huge scientific achievement, and it took the most advanced microscope ever sent into space to examine the dust particles.

Science Daily explains how much of a technical achievement it is:

It took a very long time, roughly a dozen years, to develop the device that is operating in a polar region on a planet now about 350 million kilometers or 220 million miles away.
The atomic force microscope maps the shape of particles in three dimensions by scanning them with a sharp tip at the end of a spring. During the scan, invisibly fine particles are held by a series of pits etched into a substrate microfabricated from a silicon wafer. Pike's group at Imperial College produced these silicon microdiscs.

The atomic force microscope can detail the shapes of particles as small as about 100 nanometers, about one one-thousandth the width of a human hair. That is about 100 times greater magnification than seen with Phoenix's optical microscope, which made its first images of Martian soil about two months ago. Until now, Phoenix's optical microscope held the record for producing the most highly magnified images to come from another planet.

If you look at the original Pathfinder pictures of Mars, you can see how all pervasive the dust is. The first thing you notice is that some of the rocks look like they’re underwater. On Earth, there’s no form of sediment that’s transparent like that.

To be the size it is, the Martian dust has to have been reduced to this literally microscopic size over time. That’s not unknown on Earth, but not down to sizes like this.

Dust was a problem on the Moon missions, and this Martian material is likely to be even worse.

Space Daily:

According to a NASA report that evaluates the risks of sending a manned mission to Mars, Martian dust poses as one of the biggest potential problems.

Compared to here, dust on Mars is thought to be larger and rougher, like the dust that covers the Moon. When Apollo astronauts landed there, they were covered in just a few minutes. Within hours, rough lunar dust had scratched up lenses and degraded seals.

While the lunar stays were short, if astronauts make the six-month journey to Mars, they’ll likely be expected to stay a while. That would give potentially hazardous dust plenty of time to accumulate in equipment, cause airlock malfunctions, or even infiltrate astronauts’ lungs.

The comment about the entering the lungs means a risk of silicosis or something very like it, a disease which on Earth is extremely painful and sometimes fatal. The prognosis for an affected astronaut would be critical, because the disease requires intensive treatment.

The possibilities for infiltrating equipment are the mechanical equivalent. It could completely trash vital equipment. On Earth, our comparatively gigantic dust particles are perfectly capable of playing havoc with electronics. They can also conduct static electricity. The Martian dust’s abilities aren’t known, but the possibilities are worrying.

What will be required are complete sealants to protect people and equipment, and pressurized locks to keep out the dust. It may be advisable to consider the dust as more like a liquid than dust.

One possibility for preventing scratching is an old idea, coatings of industrial diamonds on exposed materials. The diamond coating idea was originally proposed to deal with micro meteorites in the 1980s, so it would have a chance against the dust.

The problem with conventional materials, particularly manmade materials, is that tiny holes and irregularities could be scratched by the dust, and the surfaces, as they become more able to absorb dust, could take up more dust. Diamonds are much tougher, and their resistance is enormous.

Using liquid sealant fluids inside suits is another possible protection. The movement of the dust would be reduced, and any tears would freeze, probably coated in the dust, which could be a useful defence against itself.

I'm not going to comment on the organic life possibilities for the dust, because if the dust problem isn't solved, the organic life situation is academic. The Martian dust isn’t unbeatable, but it has to be beaten before we hit it. Might be worth sending up some materials to see which have the best resistance after exposure to the Martian winds.