All 12 moonwalkers had "lunar hay fever" from dust smelling like gunpowder (2018)

> And I think the outer space report was from space walks, and the explanation was that the first time the airlock itself was exposed to hard vacuum, the surfaces of the airlock would have a reaction that left a scent of ozone.

I work with industrial vacuum machinery and the big slow down in a vacuum system is coaxing out water vapor which sticks to chamber and plumbing walls like glue. My guess is dissolved oxygen in the water vapor or the water vapor itself reacting with dust particles.

But does the oxidative effect of rare short-lived impact atmospheres match the other chemistry associated with being exposed to billions of years of hard (blackbody) sunlight, solar wind, and cosmic rays on the surface of a body without much of a magnetosphere? How much are those impact oxides, particularly the ones in fine dust, shorn of their chemical bonds?

Anyone expecting to colonize Mars, or even send humans there, within the next 1,000 years is going to be sorely disappointed.

I told my neighbor: we could send some humans to Mars, but not expect to get them back!

Even if Mars were pre-terraformed, even if Mars were a perfect idyllic copy of Earth and a Garden of Eden just inviting humans to go there and set up bases, we could not send crews to Mars.

The final nail in this coffin was, for me, when I heard an ISS Expedition astronaut explain what NASA prohibits when they return from a long stretch on the Space Station. The astronauts are not permitted to jog or lift weights. They can't drive a vehicle or fly aircraft(!) They mustn't jump or twist their head around too fast. They must re-learn how to brush their teeth and how to drink fluids. They may feel dizzy, nauseous, or have trouble with spatial judgement. They are, essentially, helpless toddlers confined to their quarters. I mean, it is quite obvious by the way that they must drag these national heroes onto a gurney from the capsule after splash-down that their physiques are no longer normal.

The astronauts experience a lot of muscle atrophy and unique procedures in microgravity. If an astronaut can't even jog, or pass a roadside sobriety test, or go to the bathroom for themselves after an ISS mission, how, after 6 months' travel in deep space, will they accomplish anything at a Mars base, even mere survival?

Surely we could send up all supplies with autonomous vessels. Pre-stock water tanks and oxygen and air and have robots build a basic Mars-base there, before any astronaut arrives. But if the actual journey is practically incapacitating our actual human beings, the whole deal is off.

So no, we'll never get to Mars in the way that Musk and NASA promise. We'll keep sending robots eager to find out more and explore the interesting parts. The robots can bring back all the samples they want. They'll send pictures and even audio and plenty of sensor data. But humans will be lucky if we get a stable colony on the Moon (I believe that Moon Bases have their own currently insurmountable obstacles.) I think that humankind should be really happy and satisfied that we've got orbital space stations with continuous habitation now.

Maybe I'm not reading the right techno-utopian stuff - but I've never seen a Moon Base or Mars Base proposal which claimed to both have an actual business plan, and to project sustained profits.*

Having no prospect for sustained profits is pretty good for keep PE away.

(OceanGate Titan was a money-losing obsession project, not a viable business.)

*Except maybe the O'Neill Space Colony idea - where the Moon Base is just a Lunar strip mine, plus mass driver to throw the "ore" into orbit. IIR, they used a load of NASA's 1970's "lies we must tell Congress" numbers in calculating their transportation costs. And their whole scenario is about half a century out of date now.

Yes, but Space is Big. The density of dust of any description (lunar or other, including residual solar system dust, comet dust, asteroid dust, etc.) is low. Relative velocities can be quite high, however, and even very small particles (sand to ball-bearing sized) can inflict significant damage. Attenuation in low-Earth orbit (where the ISS is) from atmospheric drag is also probably fairly high, so that any dust captured in such an orbit (as opposed to passing through on a one-time or high-inclination orbit) would likely enter the atmosphere fairly quickly.

That said, I've seen discussion elsewhere that lunar dust accelerated by any mechanism (impacts, or rocket fire) won't billow as dust does on Earth, but will launch on a ballistic trajectory. Whether that's suborbital, orbital, or (lunar) escape velocity depends on the initiating event.

We've found numerous lunar and Martial fragments as Earth-impact meteorites, with various sources giving 200--400 known Martian fragments:

https://www.sciencealert.com/almost-200-fragments-of-mars-ma...>

Lunar dust liberated by impacts is all but certainly a component of near-Earth space dust, but probably a small percentage based on a quick search. Most seems to be of comet or asteroid origin.