Astronauts being ‘allergic’ to Moon dust wasn’t something that NASA had really planned for.
Gus Grissom, a member of NASA’s first group of astronauts, had almost been disqualified from the selection process back in 1959 when it was realised he had hay fever, but he was allowed to continue when he (rightly) pointed out that there wouldn’t exactly ‘be any ragweed pollen in space’.
That was that, NASA thought. Or, at least, that was that until 1972, when Jack Schmitt landed on the Moon.
Schmitt is notable for being the only professional scientist to walk on the Moon to date.
A PhD geologist trained to be a pilot rather than a pilot trained to be a geologist like the other eleven Moonwalkers, Schmitt had been involved in helping astronauts prepare for their missions even before he was selected as an astronaut himself.
At the end of Schmitt and Cernan’s first EVA in the Moon’s Taurus-Littrow Valley, they returned to their lunar module and removed their helmets, beginning to brush off the layers and layers of dust that had accumulated on their spacesuits.
As they did so, Schmitt started sneezing and his eyes began watering.
“Sounds like you’ve got hay fever sensors, as far as that dust goes,” said CapCom Joe Allen back in Mission Control, noticing that Schmitt also sounded congested when he spoke.
“It’s come on pretty fast just since I came back,” Schmitt said. “I think as soon as the cabin filters most of this out that is in the air, I’ll be alright. But I didn’t know I had lunar dust hay fever.”
Created when micrometeorite impacts shattered pieces of rock, and with no wind or flowing water to smooth or erode its edges, Moon dust is sharp and abrasive. It’s no wonder that inhaling it would cause Schmitt irritation.
It wasn’t an isolated incident, either. Although Schmitt’s reaction was the most pronounced, all twelve astronauts who walked on the lunar surface reported some sort of annoyance with the dust.
Moon dust clings to just about every surface it comes into contact with. It can settle behind switches and interfere with electrics, jam the zips on spacesuits, even cause radiators to overheat. If not dealt with properly, it could lead to the ruining of entire mission plans.
In a document titled ‘Risk of Adverse Health Effects from Lunar Dust Exposure‘, NASA suggested that an ‘exposure standard’ might be necessary in the future to ‘limit the amount of respirable airborne lunar dusts to which astronauts [would] be exposed’ and to limit irritation to their lungs.
NASA is currently testing means of dealing with dust with an eye to longer stays on the Moon’s surface as part of its upcoming Artemis programme. It is certainly something to keep an eye on.