The NASA is planning to send new astronauts to the moon in 2024, five decades after the last Apollo mission, which took place in 1972. Science and technology have evolved apace since then, but there are still many mysteries to be unraveled when it comes to the environment space For Artemis missions, scientists are concerned about an issue that has not affected previous visits to the surface of the natural satellite: the danger of astronauts getting electric shocks on the moon.
The case is similar to something we can experience here on Earth: When you walk on a carpeted floor, you lean on a doorknob to open a door when you are suddenly shocked. The difference is that, on the moon, just being on the surface is enough to electrically charge the spacesuit and any other object that is in contact with the ground.
Exposed to the solar wind, the lunar surface has a natural electrical charge. On Earth, the magnetic field protects us from these energized particles ejected by the sun. The moon has no such protection, so electrons and ions leave the surface electrically charged. Added to this is the fact that the lunar dust , also charged, sticks to everything that touches the surface – and the problem only gets worse.
“Moon dust will always stick to every surface no matter what you do”, said physicist Joseph Wang. According to him, dust can act as an element that drives electrons. Sticking to the space suit, this can lead to shocks in equipment that may crash or simply scare astronauts at least.
Apollo had no problems
According to Jim Rice, a senior scientist at the Arizona Institute of Planetary Science, there were no reports of electric shocks during Apollo moon missions, nor problems with lightning strikes on equipment. Wang, in turn, explains that this happened because of the areas where the missions landed, always in places bathed in sunlight.
Oops, wait there. But isn’t it just the solar wind that throws charged particles on the moon’s surface? Sunlight itself does not carry any electrical charge, but photons can cause a photoelectric effect that positively charges some electrons, balancing with those negatively charged by the solar wind. With this balance, electric shocks are less common.
The Artemis program, however, aims to land on the south pole of the moon, where the sun’s rays do not shine so directly. In this area, solar wind electrons predominate, and weaker sunlight can’t balance the game. According to a survey by Wang, shaded regions can be as high as “hundreds to thousands of negative volts.”
Rice, on the other hand, does not believe that the danger of astronauts getting electric shocks is a big problem. For him, the problem is that we do not know what would happen if these astronauts move around the moon with loaded materials and equipment.
Tests indicate astronauts may have problems
Wang and his team decided to take a test to find out if moon dust could influence electric shocks. They took samples of Gore-Tex, which is the fabric used in space suits, and placed them in a vacuum chamber with a lunar regolith simulator. Some samples were also covered with dust, while others were clean.
Hence, the researchers discharged plasma in these samples to see if they would be vulnerable to the electric arc. As expected, the dust-covered samples arched more often than those that were clean. Even so, Wang is still unsure if this could indicate any danger.
“We have shown that bows can occur in special suit material in a plasma environment that simulates the lunar surface,” said the physicist. “The next question is: can these bows damage the spacesuit?” He said, still without the doubt. Research is continuing as the 2024 Artemis mission, with humanity’s return to the lunar surface, approaches.
At the same time, NASA itself is studying a way to prevent moon dust from sticking to the special attire of astronauts going to the moon in the next decade.