Lunar dust..
Before talking about lunar dust and its danger, we will quickly talk about the lunar surface and how it is formed:
It is known that the possibility of an asteroid, meteor or meteor falling on the surface of our planet Earth is far greater than the possibility of it falling on the surface of the moon due to the strength and size of the earth’s gravity, and the weak lunar gravity, which reaches one-sixth of the strength of earth’s gravity.
Despite this, you notice with normal vision thousands of craters and craters on the surface of the moon, clear to the eye, in the form of slightly dark areas, distinct on the face of the moon that always faces us, while there are only about 180 meteor craters recorded on the surface of the earth.
? What is the reason for that in fact
Both our planet Earth and its satellite, the Moon, have been subjected to an intense fall of meteorites and meteors, and to many collisions of asteroids crossing the Earth's orbit since their formation 4.5 billion years ago, especially in the first period of formation (mass growth stage).
However, the earth by nature is subject to many changes that erase almost all traces of collisions and places of fall on its surface
The surface of the moon
While the moon lacks the presence of such changes on its soft earthy surface, and for this reason, the effects on its surface remain clear over time for every shock or impact it was subjected to, even if it was considered a light or simple shock.
Composition of lunar soil
The lunar soil that covers its surface and is composed of pieces of rock and crushed and broken stones, as a result of millions of meteorites impacts and falls.
Because of the large number of meteorites falling and the heat resulting from the continuous collisions, the lunar soil melted in many locations, then shattered again with a subsequent collision, and the matter was repeated millions of times over the life of the moon, which brought the lunar soil or what is called (lunar regolith) to its composition Soft, sharp and metallic particles do not support the existence of life, but now represent one of the main obstacles to establishing bases on the surface of the moon, as intended by the European Space Agency.
The study showed that lunar dust particles are the cause of respiratory cancer, due to the presence of hydroxyl compounds and silicates among its components.
By using lunar samples that reached Earth from the first flights of the Apollo program, a lot of information was extracted about the composition of the lunar surface and the composition of the lunar soil, which contributed to explaining the subsequent injuries suffered by the moon astronauts.
Lunar dust components
During the Apollo program, the astronauts noticed that the lunar dust has a high ability to stick to objects, much greater than the usual fine dust on Earth, and when they landed on the moon, and after a short time, they were overwhelmed by this fine lunar dust.
Dangerous lunar dust
Major (Buzz Aldrin) wrote in his detailed report after returning from Apollo 11 in 1969 about lunar dust:
“The more time you spend on the moon, the more dust you get.”
?Why are there craters on the moon
Because of this softness of the lunar soil, and the absence of an atmosphere and thus the absence of winds or erosion factors, we find that the surface of the moon represents a preserved record of everything that has landed on its surface, for millions of years.
Even the traces and footsteps of the astronauts who landed and walked on the surface of the dusty moon are still visible there to this day.
Raised meteorites on the surface of the Earth
Three phenomena exist on the surface of the Earth that enable it to hide the effects of meteorite collisions to which it is exposed, namely:
1_ Natural erosion, this phenomenon that takes place thanks to changes in the weather, water, winds, and vegetation, which are elements that are not present in the moon because it does not contain an atmosphere or water, of course. This explains the absence of these natural phenomena on its surface.
2- Movements of tectonic plates: they are continuous movements of the Earth's inner lithosphere.
And lead to the formation of new rock layers and the disposal of old rocks, and the surface is constantly changing.
From all of the above, we conclude that the planet can recycle its surface many times.
While the moon did not witness any tectonic movements of the crust for a long period estimated at millions of years, which is a long and sufficient period for the formation of craters and the effects of the collision on its surface, and their remaining visible to the observer.
3_ Volcanoes and seismic activity on the moon
Volcanic flows of lava and rock would cover the impact craters
But its importance is less on the surface of the moon, in addition to the importance of recycling the crust, as is the case on Earth
Phases of the formation of the moon
In the past, in the early stages of formation, the moon witnessed large and continuous volcanic flows on its surface that covered many large monuments, but in the recent period of stability, it did not witness volcanic phenomena for about 3 million years.
Abstract: The moon is subjected to fewer collisions than the Earth is exposed to, but it is unable to remove their effects after they are caused on it, so large numbers of craters and gaps appear on its surface, while we only notice some of them on the surface of the Earth.
Lunar craters
Below are pictures of the most important lunar craters resulting from the fall of meteorites
La lune est née
Il existe de nombreuses théories et hypothèses sur l'origine de la lune, mais les plus importantes sont :
1_ La théorie de la croissance de masse graduelle, qui explique la formation de la Terre et de la Lune en même temps à l'intérieur du premier nuage de nébuleuse solaire, et la Lune était sur une orbite proche de la planète Terre nouvellement formée.
2_ La théorie de la capture gravitationnelle, qui considère que la lune est sur une orbite éloignée de la Terre au sein des composants du système solaire, les multiples planètes et astéroïdes, et s'approche de la gravité terrestre et de sa famille pour orbiter autour d'elle, sous l'influence de son champ gravitationnel.
3_ La théorie de la grande collision : avec un astéroïde qui passe, et cette théorie croit qu'un astéroïde de grande masse est entré en collision avec la planète Terre, et cette collision était si énorme que des roches et des blocs de la croûte terrestre, et ce qui restait de l'astéroïde a volé dans l'espace entourant la terre pour orbiter autour d'elle, sous la forme d'alors, des fragments de roche et de la poussière se sont peu à peu condensés et rassemblés en un corps rocheux, la lune.
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