For chemical specialist George Aldrich, his keen sense of scent doesn’t just make him an expert—it acts as NASA’s first line of olfactory defense. As the organization’s self-described “Nasalnaut,” whose nose is government-certified three times a year, Aldrich conducts toxicity tests on all objects before they’re sent into space. In his forty-odd years working at the agency’s White Sands Test Facility’s Molecular Desorption and Analysis Laboratory, in New Mexico, he has completed more than 800 “smell missions” to detect potentially noxious and unpleasant smells that might harm or distract astronauts from completing their missions—or, more importantly, tamper with the delicately balanced internal climate of a space shuttle’s confined quarters. After all, you can’t just crack a window when you’re hurtling through outer space.

Aldrich has earned many nicknames for his very particular professional duties over the years—including “Chief Sniffer,” “Nostrildamus,” and “Most Smella Fella”—and was deemed the “best nose in the world” by Stan Lee’s Superhumans television series. On the show, Aldrich tested his capabilities against the tasks of a trained K-9 police dog, which can smell 100 times better than humans, and prevailed each time, to even his own astonishment. Nothing gets past his nose, on the job or off, except for the actual astronauts themselves. As Aldrich has said: “Human beings stink, and there’s not too much we can do about it.”