"earth"

For humans, the universe is too dimensional for us to see the details of its depths for the time being

The universe is so big, but man's range is so small that the furthest man has been so far is the moon, which is only 380,000 km away from earth on average. Of course, humans have also launched all kinds of probes, and if you include them, the range of human activities is much larger.

If humans evolved from the forest archaeopteryx, how did the forest archaeopteryx emerge?

The earth has been spinning since its inception and has been doing so for 4.5 billion years now, so why has it not stopped yet?

Although the Earth is just a "grain of dust suspended in the sun" in the universe, for us humans, this "grain of dust" is irreplaceable.

In our solar system, there are 2 planets in the habitable zone of the solar system, one of which is our home planet Earth, and the other is Mars

The earth was born more than 4 billion years ago, when it was very different from the earth of today, one of which is that the environment of cosmic space is more different.

The legendary prehistoric civilization is not the only one "Atlantis", then this mysterious "yellow brick road" could be the remains of some other prehistoric civilization left behind?

Earth is the only home we have in the universe and the only planet we know of so far that has life on it, and because of this, we usually think of it as a perfect planet.

A rigorous discussion of the unknown is not possible, so it is necessary to narrow down the universe we are discussing to only the universe we can see