For most scientists, going up to visit the Moon would be a life-long dream and the pinnacle of their career - but what happens if you get up there and find you're actually allergic to it?
Well, this exact scenario happened to Apollo 17 astronaut Harrison H. Schmitt, who found out he was allergic to the Moon while still in space.
Schmitt, 87, is the most recent living person to have walked on the Moon and is also the only scientist and person without a background in military aviation to do so.
However, he recalled that it wasn't all fun and games up there, as he found out he was allergic after breathing in some Moon dust.
Schmitt walked on the Moon in December 1972 in the final crewed mission before the Apollo program ended, and was there to collect samples of rocks near the Taurus-Littrow valley, close to the Sea of Serenity.
He made the discovery that he was in fact allergic to the dust after returning to the landing module while still on the surface of the Moon, after particles got distributed around the cabin from his suit.
Schmitt said at the Starmus space festival in 2019 as reported by The Telegraph: "First time I smelled the dust I had an allergic reaction, the inside of my nose became swollen, you could hear it in my voice.
"But [...] gradually that went away for me, and by the fourth time I inhaled lunar dust I didn’t notice that."
While Schmitt may have needed to pack a few antihistamines in his baggage for his space trip, apparently being allergic to the Moon could be more common than you'd expect.
He revealed that a flight surgeon was also affected when taking the suits out of the command module and had to stop work due to how strong his allergic reaction was, meaning that potential Moon allergies could have implications for future missions to the lunar surface.
Schmitt added: "For some individuals we need to find out whether they are going to have a reaction, if they are going to be exposed chronically to Moon dust.
"Now my suggestion is don’t ever let them be exposed to lunar dust and there are many engineering solutions since I was flying to keep dust out of the cabin, to keep it off the suit. It’s going to be primarily an engineering problem."
In fact, according to the European Space Agency (ESA), all other astronauts have suffered from "lunar hay fever" to some extent, with the symptoms generally being mild sneezing and nasal congestion which got better quickly, however some experienced symptoms for several days.
Scientists are trying to figure out what causes the issue, and believe that static on the surface of the Moon could be part of the problem.
The ESA explained that on Earth, particles get smooth out by erosion from the wind and water, while the Moon doesn't have these conditions so dust remains sharp and spiky, and as the Moon doesn't have our atmosphere to protect it from radiation, the soil becomes statically charged which can send the spiky particles into the air and make them more likely to coat equipment as well as get into the lungs.
Moon dust is so abrasive in fact, that Nasa experts found that on returning to Earth, it had worn through three layers of "Kevlar-like material" on Schmitt's boot.
There are also concerns about future astronauts inhaling the dust, which scientists have found resembles silica dust which can cause silicosis - a long-term lung disease caused by inhaling lots of crystalline silica dust, usually found in those who work with stone, rock, sand, and clay materials.
When they are inhaled, they can get stuck in the tiny air sacs of the lungs and cause scarring and inflammation, leading to a pneumonia-like condition.