Why do astronauts describe the smell of space as strong, metallic, and unique?

[WhoWee]

A recent news article quoted Astronauts as saying space has a distinct smell - "strong, metallic, and unique", also "gunpowder or ozone". Can anyone explain this?

http://news.yahoo.com/s/space/20090905/sc_space/spacesightsandsmellssurpriserookieastronauts

"WASHINGTON - For rookie astronauts flying aboard the International Space Station, the food is good, the rocket thrusters are loud and there's an odd tang in the air - apparently from outer space.

"It's a very, very different environment than I expected," Discovery shuttle pilot Kevin Ford, a first-time spaceflyer, said from orbit late Friday.

One of things Ford wasn't ready for is the weird smell.

"From the [spacewalks] there really is a distinct smell of space when they come back in," Ford said from the station in a Friday night news conference. "It's like...something I haven't ever smelled before, but I'll never forget it. You know how those things stick with you."

In the past, astronauts have described the smell of space as something akin to gunpowder or ozone.

The sounds of spaceflight have also been surprising, especially when Discovery fires up its large maneuvering thrusters, Ford said.

"It definitely gives the shuttle a kick and you just feel a little twang throughout the whole orbiter when they're firing to keep you in position," he added.

Of the 13 astronauts aboard the International Space Station and docked shuttle, nearly half are taking their first trip to space. For some, it's a short trip aboard the shuttle, which blasted off last week with three rookies aboard.

Other first-time spaceflyers are on the station for the long haul. Some have already been there for months, so the term "rookie" barely applies.

"The food is wonderful," said rookie astronaut Nicole Stott, who arrived at the station Sunday on Discovery to begin a three-month stay. "Of course we have a mix from all the partners now."

The result, she said, is a sort of orbital smorgasbord that includes food from the United States, Russia, Canada, Japan and Europe.

"I think you can find something for everyone," Stott said.

Discovery's seven-astronaut crew is in the middle of a 13-day mission to deliver fresh supplies and new science gear to the space station. The astronauts ferried Stott to the outpost to replace another NASA astronaut who will come home on the shuttle.

They also delivered a $5 million treadmill named after comedian Stephen Colbert.

Even some of Discovery's grizzled veterans were surprised by the life aboard the station, which is the $100 billion product of 16 different countries.

"It's really awesome to see all the work that's been achieved up here since our last flight," said Discovery commander Rick Sturckow, who is making his fourth flight to the station. "They've added a new solar array and some new modules. The station is something that all the international partners can be very proud of for their contributions.""



and,



http://www.sindhtoday.net/news/1/47821.htm

"Washington, September 7 (ANI): NASA astronauts aboard the US space shuttle Discovery have said that the smell of space, which is regarded as the final frontier, is strong, metallic and unique.

“There is one smell up here that is really unique though and that is the smell, we just call it ‘the smell of space’,” said NASA engineer and astronaut Gregory Chamitoff, who is on board US space shuttle Discovery.

“I haven’t had a chance to do a spacewalk yet, but when the other guys did and they came back in, there’s this really, really strong metallic smell,” he added.

For rookie astronaut Kevin Ford, Discovery’s pilot, both the sounds and smells of space have surprised him.

“It’s like something I haven’t ever smelled before, but I’ll never forget it,” he said. “You know how those things stick with you,” he added.

Chamitoff and Ford are among 13 astronauts on board the International Space Station and US space shuttle Discovery.

Astronauts from Discovery have concluded a third and final spacewalk, installing new equipment on the International Space Station (ISS), though failing to connect some of the cables.

The spacewalkers deployed a new payload attachment system, replaced a failed gyro assembly, installed two GPS antennae and did some work to prepare for the installation of the Node 3 “Tranquility” module next year.

Built in Italy by the European Space Agency, Node 3 “Tranquility” is scheduled to be flown to the ISS next February.

It contains the most advanced life support systems designed to recycle waste water and generate oxygen. (ANI)"

 

[Chronos]

Perception is in the mind of the observer. In a strange environment, strange sensory experiences cannot be ruled unusual. They are not 'smelling' space, for there is nothing there to 'smell'. More likely they are smelling emissions from equipment on the station.

 

[ikkyu]

It may be the smell which come from the space suit after it has been exposed to vacuum and radiations from the space. I think they actually has smell "something", not a sensory perception problem.

 

[marcus]

It may be the smell which come from the space suit after it has been exposed to vacuum and radiations from the space. I think they actually has smell "something", not a sensory perception problem.

I agree. What you say sounds reasonable. Not knowing the spacesuit materials and technology, I can only speculate in a very loose way.

One thing that occurs to me to ask is about the lifesupport breathing system that the spacesuit is equipped with.

Does this involve venting the used air, or does it involve recycling the air that the person breathes?

If it involves recycling the air then the spacesuit itself must be equipped with a chemical unit that removes CO2 and adds oxygen. Otherwise CO2 would build up in the air.

One chemical way to remove CO2 might be to pass the air over an oxide of potassium like K2O4. This oxide exists. Possibly also K2O5 exists, but I am not sure.
This would probably react with CO2 to form potassium carbonate K2CO3 and would release oxygen.
It might also introduce a slight odor, like of ozone or some potassium salt. However this is a very very loose speculation on my part.

The trouble is, these people are experts. If there is some simple obvious explanation like the smell is coming from the suit's own lifesupport module then they would have thought of that explanation already and they would not be talking about "smell of space".
So I don't know.

 

[WhoWee]

The trouble is, these people are experts. If there is some simple obvious explanation like the smell is coming from the suit's own lifesupport module then they would have thought of that explanation already and they would not be talking about "smell of space".
So I don't know.

This is precisely why I posted - they seem perplexed.

 

[paw]

I think 'smell of space' is a contraction of 'smell of the myriad technological systems and materials needed to keep fragile organic organisms alive inside an aluminum can in low Earth orbit'. It's a lot easier to say.

It definitely doesn't refer to the 'smell' of the vacuum of space which by definition has no smell.

Another point to remember, astronauts are not experts in all fields. Most have expertise in one or possibly two fields. It's unresonable to expect a systems engineer or a molecular biologist to immediately identify a chemical odor. Even a chemist might need time to identify it.

Having said all that I'd venture ozone is the leading candidate. There's plenty of electronic equipment operating inside a closed oxygenated system. Ozone is often described as a pungent and metallic smell.

 

[WhoWee]

It doesn't seem likely, but do you think "space dust" could be attracted to space suits and have a latent odor?

http://news.nationalgeographic.com/news/2003/08/0827_030827_spacedust.html

 

[turbo]

It doesn't seem likely, but do you think "space dust" could be attracted to space suits and have a latent odor?

http://news.nationalgeographic.com/news/2003/08/0827_030827_spacedust.html

Not such a bad idea. The zone that ISS orbits in is not rarified like intergalactic space, and stuff that is out there is bombarded with ionizing radiation from our Sun and could easily be differentially attracted to the astronauts' suits. Even the IGM (Inter-Glalactic Medium)is not so rarified that it cannot be imaged by our technology.

 

[S.Vasojevic]

If it is a suit they would simply tell that suit has an odor, and probably that would be smelly on the Earth as well.
But remember to get O3 molecule you need high energy photon smashing at O2 molecule, and those are quite frequent in empty space above earth. It maybe that part of dioxygen they are breading is being transformed to ozone. But then again ozone is not so healthy to inhale, so NASA would know about it.

 

[DaveC426913]

I really don't understand what the fuss is all about. Is there some indication/attempt to isolate the myriad materials used in a space station and space suits from the experiment?

I think this is just a feel-good story, to help the population feel connected to the space mission.

 

[mgb_phys]

One of the things mentioned by the Skylab astronauts was that they missed smells and they would inhale the lemon scented towel things they got with their meals because it was the only scent present.
This was in the days when they ate tasteless food out of tubes instead of having real food on the ISS.