The distance between the moon and the earth is just right, just covering the sun. Is it a coincidence that it is so precise?
Yes, it is a coincidence! But it is not the kind of mysterious coincidence that we generally think. For example, there is a certain force that specifically put the moon in this position, and the moon in this position is conducive to the birth of life on earth, or is more conduciveThe emergence of humans;
It is specially designed for humans.
It's not such a mysterious coincidence, but coincidentally, human beings just appeared in this period, just seeing the existence of a special relationship between the sun, the earth and the moon.
The current position of the moon from the earth just so that it looks basically the same size as the apparent diameter angle of the sun in the sky.
About 0.5°, how big is it at this time? You stretch out your arm and put your little finger in the sky. The angle of half of it is about 0.0014 times the 360° of the sky, which is 0.5°.
Why does the moon and the sun look the same size? That is, when a total solar eclipse occurs, it just covers the disk of the sun. It doesn't look too big or small, just right.
Because the current distance between the sun, the moon, and the earth has such a relationship, the true diameter of the sun is about 400 times that of the moon. The sun is indeed very large, but the distance between the sun and the earth is exactly the distance between the moon and the earth.400 times.
This makes the two of them look the same size. So how does this special relationship form?
This starts with the formation of the earth and moon system.
Most planets in the solar system and celestial bodies with relatively large masses have their own satellites. The world outside the asteroid belt, especially the four gas giants, has an absolute number of satellites in the solar system.
The only four rocky planets in the solar system are Earth and Mars which have their own satellites.
At present, we believe that the formation of satellites is nothing more than these four ways:
During the process of forming planets, the primitive matter of the solar system also formed some celestial bodies with lower masses, which later entered the orbit of a large planet and became a satellite. It itself belongs to the primitive matter of the solar system and is a gas giant planetary satellite.Main source.
The other is from celestial bodies outside the solar system. After entering the solar system, they are captured by the planets of the solar system and form satellites.
Secondly, some relatively small natural satellites are formed in the accretion disk around the planet, that is, the planetary ring.
The last one is after celestial body impacts, a large amount of debris is produced, and then satellites are formed in planetary orbits. This is the main source of rocky planetary satellites in the solar system.
What about the moon? Obviously it belongs to the last type. The two satellites of Mars also come from this. What is the evidence? The lunar samples collected by Apollo 11 show that the moon and the earth’s crust have the same material source and the density of the moon.The smallness also proves that the moon comes from the earth's crust.
New Horizons’ research on Mars and a 2016 paper also pointed out that Mars’ satellites also came from the impact of Gulai, and there is evidence that Phobos was installed at that time, but it eventually fell back to Mars.Only two satellites have survived so far.
Therefore, the generally accepted way of origin of the moon is caused by the collision between the earth and a planet similar to Mars about 4 billion years ago.
The collision caused a large number of material fragments, most of which fell back to the earth. For millions of years, the earth suffered from meteorite accretion all day, and some of the material condensed into the moon in orbit, and the surface of the moon was alsoSuffered a lot of impact and left a pocked face.
Now the special distance between the moon and the earth causes us to see a relatively special celestial phenomenon, which is a solar eclipse, which is considered to be a total eclipse, partial eclipse and ring eclipse.
These three different celestial phenomena are caused by changes in the relative position and distance between the moon and the earth. When the moon is at perigee, it happens to pass through the line between the earth and the sun. Then the moon will block the sun and letPeople in certain areas see Whole Foods.
When the moon is not strictly in a straight line with the earth and the sun, when the moon passes between the sun and the earth, the penumbra is cast on the earth, then people who pass the penumbra can see the partial eclipse.
When the moon happens to pass the line between the sun and the earth, but is not at perigee, the moon looks smaller than the sun’s disk, so we will see an eclipse.
This is the solar eclipse celestial phenomenon that occurs between the moon, the earth and the sun due to a certain distance. But this is not always the case. When the moon was first born, if there were people on the earth at that time, you would see different celestial phenomena.
About 4 billion years ago, the moon was very close to the earth. We will see a huge moon. At this time, the rotation of the earth is also very fast. There are only 6 to 8 hours a day, and 1500 days a year.
At this time, there will always be a total solar eclipse on the earth, there is no so-called partial eclipse or annular eclipse, because the moon's disk is very large, it will always cover the sun from different angles, making the global daytime dark.
But with the passage of time, the tidal gravitation of the moon caused the slowdown of the earth's rotation speed, but at the same time the earth passed its own rotation to the moon and the moon was gradually moving away from the earth.
Knowing that it takes 23 hours, 56 minutes, 4.09 seconds for the earth to rotate today, and the moon is now far enough from the earth, with an average distance of 380,000 kilometers, and is far away from the earth at a speed of 3.8 centimeters per year.
At this rate, 570 million years later, the earth will experience the last total solar eclipse, that is, by then the apparent diameter of the moon in the sky will be significantly smaller than the sun, and it can no longer completely cover the sun's disk.
In hundreds of millions of years, the phenomenon of partial eclipse will disappear completely, causing us to see only an annular solar eclipse. It is the same as the large solar eclipse currently seen on Mars.
Therefore, the distance between the moon and the earth has been changing since its birth, and the changed distance is developing according to certain physical laws.
Coincidentally, humans have unexpectedly appeared at a time when it is now as big as the sun looks, and we see this special distance.
Do you think this is a coincidence? If there were no humans, who would care if the moon would just cover the sun.
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