Although the moon, which is 380,000 kilometers away, is the only natural satellite of the earth, although it has accompanied the entire human civilization, we actually do not know about it.
So far, only the United States has carried out six manned lunar missions from 1969 to 1972, and 12 people have been active on the surface of the moon, and although other orbiters and landers have also launched a lot, they are all sample surveys, and the moon as a whole is still full of mystery for human beings.
For us on the earth, the bright moon in the night sky also has one of the biggest bugs, that is, we can never see the far side of the moon, and the records of countless literati and inkers for thousands of years are only the front of the moon.
Astronomers tell us that the reason why the far side of the Moon cannot be seen directly from Earth is because the Moon was locked by the Earth's gravitational tides shortly after its birth 4.5 billion years ago, causing the Moon to rotate at the same speed as the Moon orbiting the Earth, and the Moon faces the Earth with the same one at all times.
Therefore, for a long time, exploring the far side of the moon has become one of the dreams of the scientific community, but because the back side of the moon has never been able to face the earth, and thus can not communicate directly, so whether it is the United States manned moon landing that year or later their lunar probe, did not really land on the back of the moon, just took a few photos.
< h1 class="pgc-h-arrow-right" > until the emergence of Chang'e-4 in China</h1>
As the first probe in human history to soft-land on the far side of the moon, Chang'e-4 uses the Queqiao communication relay satellite to maintain contact with the ground command center, and the Yutu-2 lunar rover it carries has been working on the far side of the moon for more than 1,000 days.
And in this area called Aitken Crater, they discovered a secret
Specifically, the largest and oldest crater of the moon, which was formed 4 billion years ago and is directly 2500 kilometers, has a dense mass of metal at 290 kilometers underground, with a mass of 2200 trillion tons, which can almost be seen as a mountain of metal buried deep under the moon.
For a small object with a mass of only 1/81 of the Earth and a radius of only a quarter of the Earth, the appearance of these 2200 trillion tons of metal foreign bodies in the interior of the Moon is really not supposed, and even when this news comes out, it is also used as evidence that aliens are building secret bases inside the Moon to monitor the Earth.
<h1 class= "pgc-h-arrow-right" > the scientific community obviously doesn't think about aliens</h1>
In the eyes of astronomers, if the moon is indeed made of debris from a Martian-sized object that collided with the early Earth, then the moon is likely to inherit some of the remnants of the planet, or even its iron-nickel-rich core, as well as other metallic materials.
Or maybe this deeply buried metal mountain was melted by an asteroid hitting the moon in ancient times, because Jade Rabbit-2 also found debris from the asteroid impact nearby.
But in any case, the 2200 trillion tons of metal on the far side of the moon will most likely be exploited by humans in the future, because the gravitational strength of the moon is only one-sixth of that of the earth, whether it is as a springboard for humans to go to other planets, or as an industrial base for human beings in space, it is very convenient, and the weak gravitational force also makes it much easier to mine the lunar deposits than on the earth.
In addition to the underground metal mountain, Yutu-2 also found a dark green gelatinous substance, which was later analyzed as a product of the asteroid impact, and the rock melted and cooled at high temperatures.
In the future, with the return of Chang'e 6 to the far side of the moon, the mysteries surrounding the moon will be unveiled one by one, and Yutu-2 will have more new discoveries in the future.
It is believed that in the near future, perhaps around 2030, China's astronauts will be able to take the Long March 9 super heavy carrier rocket to the moon, leaving a footprint belonging to the Chinese on the moon, and the subsequent lunar bases and lunar projects cooperating with Russia will also shine.