An amazing fact has emerged from the data from the small unmanned Japanese probe SLIM, which successfully landed on the moon on January 20 of this year. The Japan Aerospace Exploration Agency (JAXA) has stated that one of its research missions is to “solve the mystery of the moon’s evolution,” and the results of observing the light waves reflected by rocks with a multi-band spectroscopic camera (MBC).
Olivine, which contains magnesium and iron, is said to be the main component of the mantles that make up the underground layers of solid planets such as the Earth and the Moon. Like the Earth, the Moon’s mantle makes up most of its volume, so knowing the composition of mantle-derived rocks can help us understand the Moon’s structure all in all. Furthermore, by closely comparing its chemical composition with olivine from the Earth’s deep mantle, we can trace the origin and evolution of the Moon.
As for the birth of the Moon, there is a theory that it was created when a large celestial body collided with the primitive Earth about 4.5 billion years ago (see Part 24 of this series). This is known as the “giant impact theory”, and it is thought that this collision caused much of the material of the Earth’s mantle to be scattered into space, which was then pulled together by gravity and formed the moon
If the composition of this sample analyzed with a spectroscopic camera is the same as the olivine from the Earth’s mantle, this supports the theory that the moon was formed from material that was was removed by a large celestial body that struck the Earth.
Rocks that came from the mantle
On the other hand, if the composition of olivine is completely different from cloth material, which makes up 80% of the Earth’s volume, the Moon was created by pulling material from space. In any case, the lunar rocks brought back by the US Apollo mission did not contain olivine, so the landing at SLIM made it possible to obtain the long-awaited precious sample for the first time hour.
When meteorites hit the surface of the moon and created a crater, they came out of the earth…
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