When you contemplate all the skills involved in sending someone into space, you think about math, physics, rocketry, and orbital dynamics. Odds are that you didn’t spend a lot of time thinking about the importance of how things smell. NASA believes it makes a lot of sense to think about a lot of scents. That’s why, for almost fifty years, the space agency has employed the services of a Chief Sniffer.

George Aldrich is a chemical specialist, working at the NASA White Sands Test Facility since 1974. In this capacity, he serves as NASA’s “Chief Sniffer,” testing the smells of everything that will go into space and interact with astronauts.

The concept of having someone test everything’s odor came after the Apollo 1 tragedy. Aldridge explained, “[After the death of three astronauts,] NASA went back and decided to do material testing, especially in 100 percent oxygen environments. Test #1 in NASA language is flammability. Test #6 was odor. They didn’t want the astronauts to be interfered with by an obnoxious odor. Test #7 is toxicity. All this was decided after the Apollo fire in 1967.”

Despite all of the sophisticated equipment on spacecraft, the human nose is one of the most reliable indicators that something is wrong in the environment. Additionally, bad smells can significantly impact the quality of life in space. Think of how unpleasant your kitchen can be after burning popcorn in the microwave or how oppressive your car can be if someone leaves a pair of sweaty sneakers in the back seat. Now imagine what it would be like if you did not have the luxury of opening a window to air out the offensive aroma and had to put up with that smell day in and day out.

Aldrich’s job is to make sure there are as few smells as possible to distract the astronauts. To that end, he has conducted more than 850 smell missions for NASA, sniffing all proposed cargo in missions related to Skylab, the space shuttle, and the International Space Station.

Aldrich tries to keep a sense of humor about his unusual job and how he describes it to others. “I came up with ‘nasalnaut,'” he said. “I wanted something cute. [Other nicknames] have come from articles. One called me the ‘chief sniffer.’ In Scientific American, the guy called the Nostrildamus.”

NASA has a lot invested in Aldrich’s olfactory abilities. An on-site nurse gives him regular check-ups and certifies him qualified to sniff. They also make sure his tests are conducted in controlled circumstances. Aldrich and his team never see an object before sniffing it. “We don’t get to see what it looks like before I smell it. I’m going into it pretty much blind. They don’t want us to be persuaded,” he explained. “We’re not allowed to look at it after we have a smell. I had a weird case just recently, actually. It was a material and it was covered… [I thought], “It shouldn’t smell like that,” and it actually smelled like butterscotch. This was a material that is going to into the suit; they are testing new materials that are going into the suit. They want to test everything for toxicity and odor in the new EV suits, the spacewalk suits.”

Smells are rated on a scale from 0 to 4, with 0 being a lack of odor and 4 being extremely pungent. “We have five people smell each material. If it has more than a 2.5 rating, it fails.”

Aldrich is frequently asked about the worst-smelling things his nose has encountered. He says, “Here’s my standard answer: Humans beings stink, and there’s not too much we can do about it. There’s flatulence, they’ve got to potty, they can stink up the place. They do try to keep themselves clean with antibacterial agents. Because of anti-gravity, they can’t take a full-fledged shower because of the water.”

Read about another career for those with sensitive noses: official armpit sniffer.

Aside from human B.O., Aldrich says there were two situations that left indelible olfactory scars in his memory. One of them was a failed refrigerator on one of the space shuttles. He said the smell was so bad that the astronauts got sick. “They double-bagged it as soon as it landed,” Aldrich recalled. “They brought it to White Sands Test Facility to do a toxicity test and it had benzene, a known carcinogen. The concentration was low enough, and we were all called in and said we don’t have to do this; it was less benzene than would smell to you fill up your car with gasoline. It failed electrically, so that’s what it smelled like. It stayed in your nose.”

The other situation he recalled was surprising: Velcro straps. “We tested them, and they stunk to high heaven,” said Aldrich. “They tested the components separately and when they slapped them together, they assumed they would pass the toxicity and odor test. When they got to space, one of the astronauts opened the velcro and they stunk the place up. On a scale of 0-4, one was 3.6 and the other 3.8. Objectionable and revolting.”

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