The Earth is a beautiful azure sphere seen from space. Humans living on Earth think they know her well enough, but do you know the following facts?

1. The Earth is not completely round

The Earth is undoubtedly a sphere, but due to the role of gravity, it is not a perfect round ball.

The polar radius of the Earth is 6356.89 kilometers, while the equatorial radius is 6378.38 kilometers.

2. Origin of Earth's name

The word "Earth" originates from the Anglo-Saxon word "Erda", which means "ground" or "soil". ".

The Earth should be called a "water balloon", because 71% of the surface of the Earth is covered by water, is the only planet in the entire universe is known to exist in liquid water.

3. Earth - days are not 24 hours

Technically speaking, an Earth Day is not a 24-hour day.

The actual time it takes for the Earth to rotate around its axis is 23 hours, 56 minutes, and 4 seconds.

4. Earth is the only planet known to have plate tectonics

Scientists believe that the Earth is made up of seven important crustal plates that move about 10 centimeters in different directions each year.

Theoretically, when the plates crash into each other, they form mountain ranges, and when they separate from each other they form canyons. In addition, they can cause earthquakes and volcanoes.

The good thing is that all of these geological movements contribute to carbon cycling and recharge, which is the basic ingredient that makes up the existence of life.

5. The Sun and the Moon

Very coincidentally, the Sun is 400 times larger than the Moon, and the distance between the Sun and the Earth is 400 times farther than the distance between the Moon and the Earth, so they appear to be equally large in the sky.

6. More than 90% of the ocean is unstudied by humans

Although mankind has set foot on the moon and has explored Mars, less than 10% of the Earth's vast oceans have been studied.

Currently, we have identified 212,906 species of marine life, but there are probably 25 million more species to be discovered.

7. The highest point on Earth is not Mount Everest

Mount Everest is indeed the highest mountain on Earth, being 8,849.87 meters above sea level.

However, as pointed out earlier, the Earth is not a perfect sphere.

Although Mount Chimborazo in Ecuador is only 6,267.91 meters high, it is theoretically 2,414.02 meters farther from the Earth's center than Mount Everest because it is located on a rise around the equator.