What was it?
Over half a century ago, in order to keep up with the proactive space exploration era, especially after the Soviet Union launched numerous probes to the Moon, the United States successfully conducted six lunar landings (from Apollo 11 to Apollo 17) to send humans to this celestial body. Twelve American astronauts have walked on the Moon.
During these historic lunar landings, a series of studies were conducted on the lunar surface, and samples of lunar soil were brought back to Earth for in-depth research.
However, the intriguing fact is that after the 12 astronauts returned from their Moon missions, experts revealed that they suffered from an “unknown illness” with similar symptoms, particularly severe nasal congestion and sneezing. This peculiar illness lasted for several weeks before subsiding.
So, what caused these astronauts to fall ill? The cause of the “unknown illness” among astronauts The mysterious illness affecting the returning astronauts from the Moon has drawn the attention of many. After conducting research on this matter, scientists gradually uncovered the truth. The main culprit responsible for this illness turned out to be the lunar dust.
Lunar dust refers to the fine particles present on the surface of the Moon. A study conducted in 2018 had previously indicated that exposure to lunar dust could harm human lung cells. When the astronauts stepped out of the Lunar Module, despite wearing their space suits, lunar dust still managed to cling to them. This occurred because the Moon’s surface and the suspended dust in the lunar atmosphere were disturbed by the landing of the Lunar Module, as well as the movements of the astronauts.
Furthermore, while the astronauts walked on the lunar surface and returned to the module, they were unaware of the presence of these particles due to the limitations at that time. Part of the reason was that the dust had dispersed within the module, subsequently infiltrating the astronauts’ bodies without the protection of their space suits.
Subsequently, the astronauts all recalled a common sensation, describing the presence of an unpleasant “gunpowder-like” smell in the air. In reality, this was the odor of lunar dust. These fine particles were even smaller than PM2.5 dust particles. After directly entering the astronauts’ respiratory pathways and lungs, they caused a mysterious illness with various symptoms such as sneezing, nasal congestion, sore throat, and even teary eyes.
These symptoms only persisted for a short period of time, but scientists wondered how lunar dust could potentially affect the astronauts’ long-term health. They also questioned whether this type of dust could pose similar issues to those caused by dust on Earth.
Why is there so much dust on the surface of the Moon?
According to scientists, the Moon has no atmosphere, and under the influence of long-term geological activities and the impact of meteorite impacts, the lunar rock gradually breaks down into fine particles. The second reason is the effect of solar wind, which causes the dust particles on the surface of the Moon to fragment and become even finer.
Astronaut Harrison Schmitt set foot on the Moon during NASA’s Apollo 17 mission in 1972. Photo: NASA.
The third reason is the weak gravitational environment of an object on the surface of the Moon, which is only 1/6 of that on Earth. Therefore, when the dust settles and encounters external disturbances, such as the landing of spacecraft or astronauts walking on the surface, it can easily be brought back into the air. Being suspended for a long time, it tends to cling to the astronauts’ spacesuits.
Harrison Schmitt, a NASA astronaut, described this mysterious condition during the Apollo 17 mission as “lunar hay fever.”
Kim Prisk, an expert at the University of California and one of the 12 scientists involved in the European Space Agency (ESA) study, said, “We don’t know how bad this type of dust is. It all depends on the estimated risk associated with future missions.”
Furthermore, researchers have found that Moon dust contains silicate, a material commonly found in volcanic areas. In fact, miners on Earth often suffer from silicosis, a lung disease caused by inhaling silicate dust.
“Moon dust particles are smaller than human hair by up to 50 times and can exist in a person’s lungs for months. The longer they stay, the greater the chance of harmful effects,” said researcher Kim Prisk.
According to scientists, inhaling Moon dust can cause damage to lung and brain cells after prolonged exposure.
On Earth, dust particles tend to become finer over many years due to erosion by wind and water. However, Moon dust is not round; instead, it is sharp and jagged.
Previous studies have shown that inhaling harmful dust particles from volcanic eruptions, dust storms, and coal mines can cause bronchitis, wheezing, eye irritation, and lung scarring. Dust particles can accumulate in a person’s airways and even penetrate into the alveoli. Additionally, dust entering the human body can damage DNA, potentially causing mutations and even leading to cancer.
To analyze the risks of Moon dust on the human body, scientists, led by Rachel Caston, a geneticist at Stony Brook University in New York, conducted experiments exposing living human and mouse cells to similar dust particles as those found on the Moon. The results showed that up to 90% of mouse brain cells and human lung cells died after exposure to this type of dust.
The study also revealed significant DNA damage to mouse nerve cells caused by this dust.
The impact of Moon dust is a significant concern for any astronaut, especially those involved in future missions to set foot on the Moon.
After returning from the Moon, the illness astronauts experience is not unfamiliar; instead, it is a normal reaction of the body. This does not mean that the Moon is toxic. However, inhaling excessive Moon dust poses a potential threat to the health of astronauts.
Currently, many countries are paying increasing attention to this issue and have begun to simulate and conduct experiments on the formation mechanism, adhesion, and dangers of Moon dust to ensure maximum health protection for astronauts.
Designing and equipping a spacesuit for lunar explorers is necessary. However, ensuring that astronauts have no contact with Moon dust is also a challenging task.
In early June, NASA announced that it will develop new spacesuits for the Artemis I mission. Two selected manufacturing companies are Axiom Space and Collins Aerospace. In addition to lunar exploration, these spacesuits will also serve for spacewalks on the International Space Station (ISS).
References for the article: ESA, Dailymail, Futurity, NASA.