"earth"

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?

It's good news that Earth has regained contact with Voyager 2 after such a long period of loss of control. But somewhat sadly, Voyager 2 is carrying very little battery power left

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 modern Earth's atmosphere is so rich in oxygen that the vast majority of this hydrogen will be re-oxidized to water without escaping from the Earth's top atmosphere

If we dig up all the sand in the Sahara Desert, then we can see the "bedrock" of this desert

In this 5.5 million-year-old cave, not only is there no sunlight, but the environment is also very harsh

Titan is the largest moon of Saturn and the second largest in our solar system, even a little larger than Mercury, one of the eight planets. Due to tidal locking, Titan's rotation period and revolution period are the same, similar to our Moon

Because Mercury does not have an atmosphere to play a role in insulation, so the temperature of the back side of Mercury can be as low as minus 172 degrees Celsius, and because of the proximity of the sun, the temperature of the sunny side of Mercury will soar to 432 degrees Celsius under the baking of the sun, so it can be seen that Mercury is simply a realistic version of the "world of ice and fire"

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.

Do UFOs exist?