Outer Space has a Smell

repapetilto writes "ISS Science Officer Don Pettit reports in his journal that outer space gives off a smell best described as "a rather pleasant sweet metallic sensation." Kind of odd considering smell is supposed to be due to volatilized chemical compounds."

Comments

Sounds Like Ozone

[eldavojohn]

When I was younger, I also arc wielded to fix various metal things around farms. I too noticed this sweet, metallic smell.

When I was a teenager I read a lot of short stories. Especially all the sci-fi & horror ones like Ray Bradbury, Philip K. Dick or Stephen King. I don't recall which one it was but a character had a train set that had a short in it on the tracks. The arcing electricity would give off this same smell. I learned through this short story that this is an incidental way to produce ozone (O3), a greenhouse gas. And that the smell is in fact a low amount of ozone. Perhaps you've detected it at the dentists office or while operating an engine? From the Wikipedia entry:

Ozone may be formed from O2 by electrical discharges and by action of high energy electromagnetic radiation. Certain electrical equipment generate significant levels of ozone. This is especially true of devices using high voltages, such as ionic air purifiers, laser printers, photocopiers, and arc welders. Electric motors using brushes can generate ozone from repeated sparking inside the unit. Large motors that use brushes, such as those used by elevators or hydraulic pumps, will generate more ozone than smaller motors. I hope he doesn't write himself off as crazy if he did detect ozone. Or at least investigate where it could have come from. If there's tiny molecules of ozone floating around in orbit of the earth, I'm certain that would be scientifically interesting. Perhaps he should test the properties of these materials when exposed to ozone, do they attract the molecules? Or perhaps he should put the materials in a vacuum here on earth for a bit and then pull them out and see if he detects the same smell?

The human nose can be an extremely strong tool for some individuals, perhaps this is more than just psychosomatic? It would drive me crazy to never investigate this if I were in his shoes. It may seem trivial but sometimes a peculiar notion is what drives scientists make a novel discovery ... or waste lots and lots of time.

Re:Sounds Like Ozone

[ivan256]

That smell is also really bad for you. The Ozone oxidizes the inside of your nose and throat. If you breathe in a large quantity, you'll get a sore throat fairly quickly, and can die after several minutes in a room with a high concentration.

I have a commercial ozone generator that I bought to use after my basement flooded to kill the mold. I had it on a timer for a while to run for an hour at night. Power went out, the timer got offset, and I went down there during the day while it was on. One lungful and I had a sore throat for a week.

Re:Sounds Like Ozone

[tenco]

Since there's an awful lot of charged particles, micrometeorites, and high energy photons bathing the astronauts while on a space walk, perhaps the smell is coming from all the ionized molecules on their suits and gear.

Origin of Ozone in the Ozone layer

Re:Sounds Like Ozone

[ivan256]

Same here.

Luckily it is also short lived. It rapidly breaks down into plain oxygen, and the smell goes away. I don't understand, though, how people can be in a room with one of those poorly made Ionic Breeze devices. They generate just enough ozone to drive me nuts. I don't even like walking by the outside of a Brookstone/Sharper Image store in the mall because of them.

Re:Sounds Like Ozone

[RDW]

'The human nose can be an extremely strong tool for some individuals, perhaps this is more than just psychosomatic? It would drive me crazy to never investigate this if I were in his shoes.'

The lunar astronauts have several theories on the (perhaps related) phenomenon of the smell of 'fresh' moondust, and seem quite interested in having this investigated further:

http://science.nasa.gov/headlines/y2006/30jan_smellofmoondust.htm

Re:Sounds Like Ozone

[gnick]

...this is an incidental way to produce ozone (O3) Arcing also produces a minuscule amount of tritium. Normally, this would be completely harmless (Yes, it's a beta emitter and shouldn't be inhaled in large quantities, but a single small arc only generates a couple of molecules...) The exception to this is when you find yourself working with spark-gap switches and somebody makes a tritium joke around an ES&H rep. It then becomes hugely hazardous because you'll find yourself spending hours doing paperwork and trying to explain radiation basics to liberal-arts graduates. This is experience talking...

Re:Sounds Like Ozone

[piojo]

"perhaps this is more than just psychosomatic?"

I would imagine so - even if somehow you were able to "smell" a complete vacuum, your own body (including the nasal passages themselves) will be giving off odors. If they are so subtle as to normally be overwhelmed by the usual natural background, that may be your first chance to detect them. Well, we get used to whatever's around. When I went backpacking for a few weeks in the desert of Utah, I stopped smelling my own B.O., but I gained the ability to smell peanut butter through two plastic bags, ten feet away. It was pretty sweet. I'm sure the same increasing sensitivity happens to astronauts who live in a mostly sterile, boring, environment.

Smell isn't caused by chemicals in the air

[Junior J. Junior III]

Smell is caused by chemicals in the air triggering olfactory receptors in our sense organs and causing sense data to be interpreted by the brain as an odor.

If you take away the sense data, the brain is still interpreting something, namely the absence of data. It could be that this odor is simply how the brain handles a null dataset.

Re:Smell isn't caused by chemicals in the air

[omfglearntoplay]

Yeah. I was thinking, after reading the title of TFA, that it was the reverse/absence of smell he was detecting. Don't try this at home, but if you clean your bathroom with a too high concentration of bleach, and it starts to hurt a little... when you leave the room (house, neighborhood) to get out of that awful smell, you will notice what i believe is the "negative smell" of bleach. And if you thought bleach was bad, omg, this "smell" which is just the interpretation in reverse is really really bad. I could be wrong on this... but I was assuming my smell sensors were doing what your eyes and other sense organs do with a constant strong stimulus. You know, like when you stare at a blue wall for a while, then look at a white wall, you see the opposite of blue (orange). I forget the name of this and am out of time to look it up.

Re:Well, that makes for a good sci fi book title

[sm62704]

from Amazon.com:Starfighters of Adumar (Star Wars: X-Wing, Book 9)

Funniest SW Book Ever, October 18, 2001
By Handofthrawn "handofthrawn45" (Cleveland, OH) - See all my reviews

Ah, the sweet smell of space combat and politics mixed with witty banter. While this is by no means the best SW book ever written, it's certainly a very enjoyable read. I've been a big fan of the X-wing series and both Stackpole and Allston. The book starts off on a very nice note: Wedge breaks up with Qwi. Ahh.... Allston must have joined the Stackpole-Zahn pact to rid the world of SW novels from all of the terrible relartionships Anderson thought up in his books.

Nothing like the smell on ISS

[untree]

Slightly offtopic, but I've heard that the air filters on ISS only scrub harmful CO2, CO, etc., but plenty of other odors persist, making you almost vomit when you first open the hatch. Of course you get used to it after a bit, but can you imagine being one of those tourists who paid $25+ million to spend a week in a fart tank?

He's writing about the *Experience*, not physics

[billstewart]

RTFA - it's really short, and was written in 2003, so you should have had plenty of time...

Of course vacuum doesn't have a smell, and it's much more likely that the smell is from the way space suits react to being in vacuum than gasses wafting up from earth getting stuck on them. Or it could be from some of those funky molds that grow on the space station. But that's not really relevant, because he's not writing about physics, he's writing about the experience of being in a space-ship, and smell is one of those things that tie in to emotions and memory.

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