What is the source of dust?

JeanTate

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By dust I mean fine particulate matter, and I'm interested in natural sources, here on Earth, but also on the Moon, Venus (if there is any), Mars, etc.

Focusing on the main sources, both immediate and indirect. And ignoring "water dust" (i.e. snow and ice), at least here on Earth.

My guess is that the main immediate sources are soil, sandy deserts, and sandy beaches. With volcanoes an important, but not major, source. Micrometeorites, salt spray, and no doubt many others are minor sources. The purely geological processes involved (i.e. ignoring the organic ones which are essential for the creation of soil; I'm interested in those which apply beyond the Earth) are thus water, ice, and wind erosion (probably in that order).

On the Moon, there's surely a lot of dust from ancient volcanoes and large impacts, but in recent times (i.e. the last ~3 billion years) it's the result of micrometeorites and their impacts. Similarly for Mercury.

On Mars?

On Venus??
 
Radiation alone impacts vacuum surfaces and heating and cooling fractures smaller and smaller particles ...dust adheres with electro-static charges....

Aeolian wind sculpting would be the major source of dust on both Mars and earth.
The amount that comes off the deserts is astonishing and makes nutrients move around the planet. It's a crazy complex system.

Salt spray is not dust unless the salt precipitates out and some small invertebrates might be from seasonal lake beds and salt pans.

Beaches not so much as they are sand not dust.

The big red centre in Australia, the Gobi, and other drylands are natural sources of dust and the manmade dust bowls very destructive.

Mars is entirely Aeolian. Venus ....who knows not likely any dust. I suppose there is ice dust on the outer planets but most won't be water ice. Dust can be anything that is not liquid..liquid version is vapour of sorts but not dust. You can have ice dust tho.
 
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macdoc said:
Radiation alone impacts vacuum surfaces and heating and cooling fractures smaller and smaller particles ...dust adheres with electro-static charges.....
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Good point. Thermal cycling is certainly a factor on earth as well.

Is it possible for dust particles in space to accrete out of molecules? Be formed in stars in some fashion?
 
macdoc said:
Space is mostly dust...I'd guess it is bulk of the mass of universe.
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No. Aside from dark matter and dark energy, the majority of ordinary matter is hydrogen. Hydrogen in space does not form dust by itself, it remains a gas or plasma. Hydrogen incorporated into molecules (such as water) can form dust, but most hydrogen is not in such molecules.
 
macdoc said:
Radiation alone impacts vacuum surfaces and heating and cooling fractures smaller and smaller particles ...dust adheres with electro-static charges....

Aeolian wind sculpting would be the major source of dust on both Mars and earth.
The amount that comes off the deserts is astonishing and makes nutrients move around the planet. It's a crazy complex system.
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Amen to that. Here in SE Greece we get regular doses of orange African dust blowing in from the S. When it's bad you can feel it in your nose and throat. If it rains when that's in the air it sits on exposed surfaces like a thin mud. It's the only time I clean our ancient car, though then only the windows ;)
 
Trebuchet said:
That's the source of most house dust, IIRC, which is kind of creepy. But since the OP seems to be looking for non-biological stuff in space, mostly impact I suppose. Erosion where applicable on planets with an atmosphere.
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Sources of house dust is mostly things like dead creepy crawlies, soil, particulate matter from outside, pet hair etc. Little house dust is from human skin.

The particulates can come from deserts (even here in the UK, we get some from the Sahara), or soil can sometimes get blown about on very dry days. We get a fair amount if particulates from burning things of course.

"Dust bares no grudges, and once removed will always return.... in a friendly way"
 
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I lived in the western portion of San Francisco for several years and was amazed to discover that there was virtually no dust compared to where I previously lived, New York City. The winds in SF are primarily west to east and off the ocean, so the only dust came from dried sea spray. But the further east one goes in the SF Bay Area the more the dust, until by the time you are in the agricultural Central Valley the dust is quite intense.

I suspect from these experiences that very little dust on hard surfaces originates from exfoliated skin. That would have be a constant anywhere I lived. Most is probably from tillered and/or wind blown soil in agricultural areas, and construction, debris, and particulates from combustion, car tires and brakes, etc. in urban areas.

I miss not having to dust for weeks on end in San Francisco!

I am not counting the hairs from my cat as dust, or my own hairs as I began to go bald.
 
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When I first moved to Shanghai there was a lot more construction going on. The amount of dust was insane. If I let my windows open the floor of my apartment would be covered in a layer of dust in a matter of hours.
 
Thanks everyone for your inputs.

Meteorites may be classed into three broad categories: iron, stony, and carbonaceous; add comets and you have icy.

Mercury, Venus, Earth, Moon, and Mars will all be impacted by all four kinds of meteors; on Mercury and the Moon, all such impacts will produce dust, even if it's predominantly pieces of the surface (icy bodies may leave some dust, as comets do contain dust). Smaller meteors will burn up in the atmospheres of Venus, Earth, and Mars; much of the vapor will condense and form dust. Larger (and must be very large for Venus) meteors will impact the surfaces ... and produce dust.

Volcanoes - of which all except perhaps Mercury have or had once - also produce dust (e.g. "ash", and "laze").

The dust produced by water and icy erosion may not be "free" until the glacier disappears (leaving moraines) or the water evaporates. A different kind of dust may be created by minerals once dissolved in water being deposited when the water evaporates; salt spray can also produce "salt dust" in a similar manner. Both Earth and Mars have dust produced by these processes (for Mars, water erosion long in the past); Mars also has dust produced by "dry ice erosion". I do not know if there are similar dust-producing processes - with a different substance than H2O - on Venus; as an aside, Titan surely has similar processes (not water), as does Enceladus (water).

Wind erosion also produces dust, on both Earth and Mars; Venus?

Thermal cycling too.

I wonder how dusty the surface of Io is?
 
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