An unexplained illness that all astronauts who have set foot on the Moon have experienced, with a variety of symptoms and some cases taking several days to recover.
More than half a century ago, to keep up with the proactive exploration of space, especially after the Soviet Union launched several probes to the Moon, the United States conducted six successful landings (from Apollo 11 to Apollo 17) to send humans to this celestial body. A total of 12 American astronauts have walked on the Moon.
These six historic landings conducted a series of studies on the lunar surface and collected samples of lunar soil to bring back to Earth for in-depth research.
However, what is strange is that after the 12 astronauts who participated in the Moon landings returned to Earth, experts revealed that they suffered from a “strange illness” with similar symptoms, especially nasal congestion and severe sneezing. This peculiar illness lasted for several weeks before resolving.
NASA astronaut Harrison Schmitt described a mysterious illness known as “lunar hay fever” that affected the 12 astronauts on Apollo 17. The symptoms ranged from sneezing to nasal congestion, sore throat, and watery eyes, sometimes taking several days for the reactions to ease.
Astronauts returning from the Moon face respiratory issues. (Image credit: NASA).
Eugene Cernan on Apollo 17 covered in lunar dust. (Image: NASA).
Researchers have been unable to determine the exact cause of these symptoms, as well as the actual toxicity of the Moon. Nevertheless, studies indicate that simulated lunar soil can damage the lungs and brain cells after prolonged exposure.
“We have not fully understood how severe this dust can be” – one researcher stated. This dust may also wear down the layers of space suits and damage the vacuum equipment of the Apollo sample containers.
All of them are striving to estimate the risks for those involved in future exploration missions. One of the components found in lunar dust is silicate, a material commonly found in volcanic activity that can harm the lungs if inhaled.
Moreover, the low gravity on the Moon allows small particles to remain longer and deeper in the lungs, increasing the toxic impact.
Additionally, unlike particles on Earth that are often softened and eroded by wind and water, lunar dust is not round but sharp and frequently exposed to radiation from the Sun. Astronauts spending extended time on the Moon face the risk of DNA damage from inhaling this dust, experts warn.
Why is there so much dust on the lunar surface?
- The first reason, according to scientists, is that the Moon lacks an atmosphere. Coupled with the effects of long-term geological activity and meteorite impacts, lunar rock gradually breaks down into fine particles.
- The second reason is that under the influence of solar wind, dust particles on the lunar surface are gradually fragmented into finer dust.
- The third reason is due to the weak gravitational environment, which is only 1/6 that of Earth. Therefore, when dust settles and encounters external disturbances, such as spacecraft landings or astronauts walking on the surface, it can easily be lifted back into the air. It remains suspended for a long time, making it easy to adhere to astronauts’ space suits.
Kim Prisk, an expert at the University of California and one of the 12 scientists involved in the European Space Agency (ESA) research, stated: “We do not know how severe this dust is. It all depends on efforts to estimate the risk levels associated with future missions.”
Additionally, researchers noted that lunar dust contains silicate, a type of material typically found in volcanic regions. In fact, miners on Earth often suffer from silicosis due to inhaling silicate dust.
“Lunar dust particles are up to 50 times smaller than human hair and can linger for months inside human lungs. The longer they stay, the greater the chance for harmful effects,” researcher Kim Prisk noted.
According to scientists, inhaling lunar dust can destroy lung and brain cells after prolonged exposure.
On Earth, dust particles tend to be finer after years of erosion by wind and water. However, lunar dust is not rounded; instead, it is sharp and spiky.
To analyze the risk of lunar dust on the human body, scientists, led by Rachel Caston, a geneticist at Stony Brook University (New York, USA), conducted experiments with living human and mouse cells exposed to dust similar to lunar dust. The results showed that up to 90% of mouse brain cells and human lung cells died after exposure to this dust.
The study also revealed that this type of dust causes significant DNA damage in mouse neural cells.
The impact of lunar dust is a significant concern for any astronaut, especially those involved in future Moon missions.
After returning from the Moon, the illness experienced by astronauts is not unusual; rather, it is a normal bodily reaction. This does not imply that the Moon is toxic. However, inhaling significant amounts of lunar dust poses potential health risks to astronauts.
