Absence of erosion on the moon
Although we use the same terminology to refer to the “soil” on Earth or the Moon, they have little in common.
- On Earth, soil is formed by biological or chemical processes.
- Lunar soil contains no organic material.
Although radiation-induced chemical reactions determine different types of dust, lunar dust is formed purely by mechanical grinding when meteoroids impact and by interaction with the solar wind and other energetic particles.
Unlike Earth, where pebbles are rounded over time by the natural elements, making them relatively easy to handle, lunar soil is not exposed to erosion. Without wind and water to wear down their edges, lunar grains are often very sharp and angular, with freshly broken surfaces.
Sharp as glass but fine as powder, lunar dust can be less than 20 microns in size, making it highly harmful in ways we do not see on Earth.
Moon dust is volatile
Unlike on Earth, lunar dust is not compacted. Any activity on the surface can kick up buckets full of dust, but even without astronauts walking around on the surface or a lunar module setting foot on the ground, dust particles and clouds have been seen floating several centimetres to metres above the surface.
This is despite the fact that there is no wind or water flowing over the surface to lift them! Small dust particles can even be transported over enormous distances on the moon.
Scientists attribute the mobilisation of dust to electrostatic forces. Similar phenomena could occur on other celestial bodies without air, such as comets and asteroids.
