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

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

#171

Post by dotancohen »

ItsClo688 wrote: post #154
stonecharioteer wrote: post #151

Earlier quoted context omitted.

This is what trips me up about terraforming. If we learn to create an atmosphere, are we going to instantly poison the oxygen we introduce?

great questionprobably not poison it directly, but you'd lose a significant chunk to oxidation reactions before reaching any stable equilibrium. the surface is essentially a massive reactive sink. mars has a similar problem, the perchlorate in the soil would react badly with a lot of things we'd want to introduce. the optimistic read is that oxidation reactions release energy and eventually reach stability. the pessi…

Isn't Mars red due to oxygenation of the rocks? Is that ancient oxygenation or is there some quantity of oxygen in Mars atmosphere today? Does the atmospheric CO2 sometimes break down (maybe under sunlight) and release some small quantity of O2 or might there be another source? Might something underground be respirating atmospheric CO2?

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

#172

Post by bertylicious »

LorenPechtel wrote: post #73
darknavi wrote: post #32

Earlier quoted context omitted.

If this fact piques your interest, the book Delta-v by Daniel Suarez glances off this fact and uses it to justify exploring asteroid mining instead of a colony on Mars.

I'm not impressed with his science.

I'm not impressed with your comment.

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

#173

Post by gnabgib »

pitaj wrote: post #148
datsci_est_2015 wrote: post #125

Earlier quoted context omitted.

Assuming they mean the ground acts as a heat sink, and sufficiently underground you’re not subjected to the above average heat of the day and below average cold of the night.

Isn't mercury tidally locked? Day is always day, night is always night.

It is not (it has a 88d year, and a 58.65d.. day[0]) , we just had a post about it - if you travel at 4kph you can chase the sun.. A Mercury Rover Could Explore the Planet by Sticking to the Terminator (18 points, 1 week ago, 6 comments) https://news.ycombinator.com/item?id=47720941

[0]: https://en.wikipedia.org/wiki/Mercury_(planet)

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

#174

Post by everyone »

junon wrote: post #57
helterskelter wrote: post #49

Earlier quoted context omitted.

At least some ISS astronauts describe smelling burnt metal after returning from EVA, if memory serves. (Others may smell ozone, I've just always remembered hearing burnt metal).

I always heard burnt steak.

They say that about vaccum. eg. an airlock after re-pressurising it after a spacewalk. Apparently a vaccum sucks stuff like sulphur from within steel to it's surface.

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

#175

Post by verisimi »

dotancohen wrote: post #168
jordanb wrote: post #67

Earlier quoted context omitted.

There was some concern when Apollo 11 landed that when they repressurized the LEM with moon dust samples inside it would start a fire. I think they had a small test article that they blew a small stream of oxygen over to ensure it wouldn't auto-ignite.

And if the sample did auto-ignite, what was the procedure?

Empty out a glass of water and blow the floating blobs towards the fire.

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

#176

Post by singularity2001 »

stonecharioteer wrote: post #151
ItsClo688 wrote: post #144

Earlier quoted context omitted.

the detail that kills me is moon dust has never contacted oxygen in billions of years, so every time an astronaut came back inside they were essentially doing a chemistry experiment for the first time. the whole moon is just waiting to react with air

This is what trips me up about terraforming. If we learn to create an atmosphere, are we going to instantly poison the oxygen we introduce?

if the moon will be settled it will be settled by AI embodied in some kind of (nano) robot or artificially created life.

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

#177

Post by FranOntanaya »

ItsClo688 wrote: post #144
corysama wrote: post #34

I recall an article from a long time ago that basically said “astronauts report” the moon smells like spent gunpowder and outer space smell like… I think it was ozone. What they were actually reporting was the smell of the airlocks after they returned from their excursions. The moon has no atmosphere, so it has been accumulating dust from billions of years of asteroid impacts that have never come in contact with oxyg…

the detail that kills me is moon dust has never contacted oxygen in billions of years, so every time an astronaut came back inside they were essentially doing a chemistry experiment for the first time. the whole moon is just waiting to react with air

Well, sort of. Solar wind does include oxygen ions, so it's exposed to a small extent.

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

#178

Post by adrian_b »

ItsClo688 wrote: post #144
corysama wrote: post #34

I recall an article from a long time ago that basically said “astronauts report” the moon smells like spent gunpowder and outer space smell like… I think it was ozone. What they were actually reporting was the smell of the airlocks after they returned from their excursions. The moon has no atmosphere, so it has been accumulating dust from billions of years of asteroid impacts that have never come in contact with oxyg…

the detail that kills me is moon dust has never contacted oxygen in billions of years, so every time an astronaut came back inside they were essentially doing a chemistry experiment for the first time. the whole moon is just waiting to react with air

The danger is not really great.

Any dust on the Moon still consists mostly of silicates which cannot be oxidized.

When dust comes from meteorites, it contains a fraction made of iron sulfide (with small quantities of other sulfides) and another fraction made mainly of hydrocarbons.

The metallic sulfides can be oxidized, but they will not burn violently. The hydrocarbons are like a tar or pitch, because the volatile hydrocarbons would have sublimated in vacuum. So neither that tar is easily flammable.

The gunpowder smell is likely to be caused by the oxidation of the sulfides from the dust, which releases sulfur dioxide, the same like burnt gunpowder.

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

#179

Post by adrian_b »

Bender wrote: post #40
corysama wrote: post #34

I recall an article from a long time ago that basically said “astronauts report” the moon smells like spent gunpowder and outer space smell like… I think it was ozone. What they were actually reporting was the smell of the airlocks after they returned from their excursions. The moon has no atmosphere, so it has been accumulating dust from billions of years of asteroid impacts that have never come in contact with oxyg…

My UV sterilizing lights make my room smell like O3 Ozone and that smells nothing like spent gun-powder to me. The only other time I have smelled the same thing is when there has been mass lightening events in the sky. Were they talking about actual black powder or nitrocellulose? I've smelled black powder at the range when people bring out their antique rifles and that also does not smell like Ozone to me.

I assume that they talk about black powder.

The dust that comes from meteorites contains up to 4 fractions: silicates, which cannot be oxidized, metallic iron, which oxidizes, but it does not form volatile substances that can be smelled, hydrocarbons in the form of a tar or pitch, which can burn but it cannot be ignited easily, and finally a fraction made of iron sulfide (troilite) with small quantities of other sulfides.

In contact with air, the sulfides will be oxidized, releasing sulfur dioxide. Burning black powder also releases sulfur dioxide, which is the main reason for its smell. Burning pure sulfur will produce the same smell.

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

#180

Post by blub »

Bender wrote: post #133
lifeisstillgood wrote: post #119

Earlier quoted context omitted.

Sorry for the tangent, but you sterilise a whole room with UV light? Is that efficient ? Do you do it after tidying / cleaning ? Is there a medical reason for the extra part? Is it just cool :-)

The house came with a bacteria that would normally be hard to get rid of. UV, bleach and peroxide took care of it. I just repeat the process to ensure there is no bacteria or mold. This seems to bother people in this thread which I find fascinating. A part of me wants to bring my black light to their dwelling.

Was it from flooding or how did it get there? How did you detect it?
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