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When NASA chemist Julio Padilla wants to vet new “sniffers” for the agency’s odor lab, he uses what’s called the “10 bottle test.”
“Three of them are blanks, which is just distilled water with no smell, and seven others have a smell to them,” he said, lining up the small bottles.
The seven scented bottles comprise a kind of menu of strong scents — from floral and minty, to pungent and putrid — all of which come labeled only with numbers.
The job of the potential sniffers is to identify the blanks — “the most important part,” Padilla said, as it determines whether or not someone qualifies as a sniffer — in addition to distinguishing between the seven other smells. If they can do that, it means their noses are perfectly calibrated for lab-level sniffing.
Padilla offered a demo.
“All right, so start with one,” he said, and took a sniff. “Smells like ether — so I would mark it down … as being the smell of etherol.”
He gave it another sniff. “Doesn’t smell too bad,” he said. “I love the smell of ether, actually.”
The next couple bottles were harder to tell. Padilla guessed that the second bottle might be floral, and that the third one was a blank.
On the fourth bottle, he took a deep whiff — and instantly recoiled.
“Ugh! I shouldn’t have done that,” he said. “So that one’s definitely putrid. Ugh. It smells like rotten eggs basically.”
As it turns out, this test is just the tip of a very stinky iceberg at the odor lab, which is part of NASA’s White Sands Test Facility in New Mexico.
The main job is to sniff out some of the most horrible smells you can imagine, to help NASA engineers figure out how to contain them.
The smell of space You might not think there’s much to smell in space — but, according to the odor lab’s manager, Susana Tapia-Harper, space missions are known for getting pretty ripe.
“Especially space vehicles that have been in use for a long period of time, and that don’t get a lot of fresh air over that time,” she said, “there have been reports that those kind of smell like locker rooms.”
Astronaut Scott Kelly once said that the International Space Station smelled remarkably similar to a jail he once toured — featuring similar “combinations of antiseptic, garbage, and body odor.”
NASA astronaut Scott Kelly, Expedition 25 flight engineer, is pictured near three stowage bags floating freely in the Unity node of the International Space Station. (NASA) It makes sense, if you think about it. Most space missions take place in cramped quarters, which in addition to being their workplace serve as astronauts’ cafeteria, gym, and, yes, their bathroom.
“If you can imagine in space, you can’t open a window,” Tapia-Harper said. “And if there’s a stinky situation in the bathroom and it’s close quarters, so there’s not much fresh air to air things out.”
The source of some smells — like kitchen trash — can at least be tied up in a bag. But that’s not the case for all.
“There are those smells, like sweat and farts, that aren’t able to be contained,” she said, “and those do start to accumulate over time.”