People have always dreamed of flying to the moon to see what this neighbor of the earth looks like. After humans entered space, the Apollo moon landing program sent 12 astronauts to the surface of the moon. They not only explored a completely strange alien world, but also stood on the planet outside the earth and witnessed the earth with their own eyes.
So, what kind of experience is it to see the earth from the moon?
First of all, the earth will look very big, because the earth itself is much bigger than the moon. If you can see the whole earth, it will be 14 times the size of the full moon. The earth seen on the moon will also have it? Clear and round? The phase will also change continuously within a month.
What's more strange is that the earth doesn't seem to fall or rise from the moon, but hovers in the air. This phenomenon is caused by the tidal locking of the moon. Every time the moon revolves around itself, it will revolve around the earth at the same time. These two periods are completely consistent, which is caused by the tidal effect of the earth's gravity on the moon for a long time. Because of this, the moon we see on the earth is exactly the same, and the earth we see on the moon is hovering in the air.
In addition, looking at the earth from the moon may cause fear. We can't help sighing the fragility of the earth, but also the fragility of our life on it.
Seen from the moon, the earth looks very quiet, like a dazzling blue pearl. The earth is surrounded by endless dark space, as if it were in the endless abyss of the universe. Beyond the earth, there is dangerous space.
We live in this small blue spot, and human beings have thrived on the earth for generations. In the universe, this blue dot looks ordinary, but it carries everything of human beings, and our survival cannot be separated from the earth at all.
The earth is covered with a lot of liquid water and atmosphere. There is water and air necessary for human survival on the earth. The distance from the earth to the moon is 380,000 kilometers. Although not far away, they are two completely different planets. The moon is barren, with no atmosphere and no ocean. The temperature difference between day and night on the surface of the moon is as high as 300 degrees Celsius. The moon environment is a forbidden area for life, but the earth is full of vitality.
Seen from a distance, the earth is like a speck in the sea of stars. Traveler 1 6 billion kilometers away? Looking back affectionately? Captured this suspended in the vast space? Dim blue dots? ：
In the vast starry sky, the earth is now our only home. Perhaps in the future, mankind will have the opportunity to find other planets suitable for survival. Even if we can find a livable alien world, it is difficult for us to go. Because the universe is so big, it is not easy to fly out of the solar system with a radius of 1 light-year, let alone the vast universe tens of thousands or thousands of light-years away.
So far, man has not found any signs of life on other planets. On earth, the existence of life is a miracle. It is extremely fortunate that human beings can evolve and thrive on the earth.
It can be predicted that in the long years to come, the earth will still be the only place where we live in the universe. There is no way out for mankind in the universe. We should protect this precious blue planet.