OT-- Oddball question, very fine magnetic powder in the air.

I thought about mounting a light above my bench. To find the joists, I used some strong magnets to locate the drywall screws. I left the magnets in place while I thought about it. After a week or so, I took the magnets down, I found there was a very fine blackish magnetic material on the magnet. It is very fine and difficult to remove, but I worked at it until it was gone. I repeated the experiment again, a week later I see this magnetic material is on the magnet again. So I looked at the dozen or so magnets stuck to the panels on my bench, they all have the powder, but much less, and they have been stuck on the metallic parts of my bench for years. Where does such a fine ferrous powder come? This is in my home, not an industrial area. Mikek

Reply to
Lamont Cranston
Loading thread data ...

All of the magnets I have are Neodymium. Mikek

Reply to
Lamont Cranston

Outer space - seriously!

formatting link
Assuming here that you don't do arc welding in a neighbouring room...

If you look at it under a microscope it can be quite interesting. The sludge that accumulates in plastic gutters is quite rich in it. All you need it s Nd magnet to harvest it. Popular science project for children.

Reply to
Martin Brown

I'm aware of space dust, I have heard of putting a sheet on your roof to harvest it. Might be interesting to put a large electromagnet with a paper cover to harvest. Mikek

Reply to
Lamont Cranston

Do you mess with printer/copier toner?

Reply to
Jasen Betts

Black iron oxide (magnetite). It's everywhere.

Cheers

Phil Hobbs

Reply to
Phil Hobbs

But by the time it has drifted down through the atmosphere it isn't space dust any more. The very small (and very chemically active) carbon particles emitted by coal fires and diesel engines are seriously carcinogenic, but the iron oxide dust around iron mines doesn't seem to be all that bad, and iron oxide dust from burned up micrometeorites won't be too bad either.

Reply to
Anthony William Sloman

We evolved with it, maybe why we evolved! Bless the space dust. Mikek

Reply to
Lamont Cranston

On a sunny day (Sat, 19 Nov 2022 17:23:56 -0500) it happened Phil Hobbs snipped-for-privacy@electrooptical.net wrote in snipped-for-privacy@electrooptical.net:

I have several 'super-magnets', some small ones stuck to the side of a PC. Never ever encountered any black stuff on any of those. No I have an inkjet printer, not used for ages tough...

Air quality is pretty good here, and close to the sea.

formatting link
If these magnets were covered by stuff I would get TF out of there! These small ones are useful to magnetize screwdrivers and pull out screws, hold pens on the side of the PC, etc.

Reply to
Jan Panteltje

Some of the dust in space contains polycyclic hydrocarbons like benzene Buckminsterfullerenes (which were first observed in molecular clouds with a spectrum that matched nothing known at the time on Earth).

The rare carbonaceous chondrite that landed in the UK a couple of years ago contains more than its fair share of interesting organic compounds including water with similar isotope ratios to that on Earth..

formatting link
The higher abundance of L-isovaline in such meteorites is thought to be one reason why life evolved using L-amino acids as building blocks.

And a more popular science but somewhat mangled article on the BBC

formatting link
"A A" is a clueless illiterate moron. Comparison with two short planks would be insulting to the planks.

Reply to
Martin Brown

How much of that would survive the descent through the ozone layer?

with similar isotope ratios to that on Earth..

They are rare because they have to be big enough for an inner core to survive descent through the atmosphere at essentially escape velocity. They will get cooked on the way down while the outer layers get burnt off.

He is also a vociferous ignorant moron, and keeps on claiming to have worked on demanding high tech projects. His capacity to make implausible claims is up there with Gnatguy.

Reply to
Anthony William Sloman

I don't know for sure but they are incredibly rare. Probably because they practically fall apart with the slightest jolt (and will do the same in space). Spend too much time in the sunlight and all the volatile components will be lost - same way that comets and meteor streams arise.

Their remnants along cometary orbits may well be responsible for most of the meteors we see that burn up in the upper atmosphere.

Some of the software I used to do was for analysing meteorites and I know they get incredibly excited about the Europium anomaly. If present it indicates a planet that formed sufficiently to have stratified as an iron core, SiMa, SiAl crust and was then smashed to bits in a collision.

en.wikipedia.org/wiki/Europium_anomaly

Europium has radically different solubility in the different molten rock formulations so it acts as a marker for planetary formation (or not).

The nickel iron meteorites and stony ones are very much more robust than the much rarer carbonaceous chondrites which have to reach Earth PDQ and be found soon after landing if any of the interesting compnents are to survive. Amazingly for a modest sized one it mostly holds together bonded by water ice until it hits the deck whereupon it disintegrates. See the picture fig 1 in the Science article it looks for all the world like a small heap of grey cinders.

Reply to
Martin Brown

Yeah, but all you guys have is mud. ;)

Cheers

Phil Hobbs

Reply to
Phil Hobbs

I tried to get some pictures under the microscope, they don't show a lot, but here the are, second one is more magnification on the end of a sewing needle.

formatting link
formatting link
Mikek

Reply to
Lamont Cranston

Might be fly ash.

Cheers

Phil Hobbs

Reply to
Phil Hobbs

We had a coal fired power plant 5.5 miles north of us, but it stopped burning coal 6-1/2 years ago. I do live near busy 5 lane road. Mikek

Reply to
Lamont Cranston

Next time we go a week without rain, I'll take a big magnet I have and put it in a baggie with rubberband or some spacer on each end, then take it up where I have a fairly flat metal roof, and drag it all around to see what I get. Mikek PS, some of you might try putting a big magnet (maybe wrapped in plastic) in the downspout of your gutters. I don't have gutters.

Reply to
Lamont Cranston

On a sunny day (Sun, 20 Nov 2022 10:45:33 -0800 (PST)) it happened Lamont Cranston snipped-for-privacy@gmail.com wrote in snipped-for-privacy@googlegroups.com:

Second one frightens me! Are you living close to some metal processing industry? If that stuff is conductive it may well affect some electronics too!

I have read about air pollution on the coast here near a big Tata plant:

formatting link
illnesses there, would not want to live there.

Reply to
Jan Panteltje

On a sunny day (Sun, 20 Nov 2022 17:23:43 -0800 (PST)) it happened Lamont Cranston snipped-for-privacy@gmail.com wrote in snipped-for-privacy@googlegroups.com:

***I have a fairly flat metal roof***

Well that is a big hint to the origin of the stuff!! ???

Reply to
Jan Panteltje

It might just be coming from breakfast cereal!

John

Reply to
John Walliker

ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.