The Earth, the planet we depend on for survival, has a long and storied history stretching back 4.6 billion years.

If we were to condense this immense period into a single 24-hour day, the appearance of human beings would occur only at the last minute.

This stark contrast in time highlights the brevity and seeming insignificance of humanity within the Earth's vast history. As the newest inhabitants of this planet, we must respect nature, adapt to it, protect it, and strive to create a harmonious coexistence between people and the natural world.

Seven Little-Known Facts About the Earth

1. The Origin and Naming of the Earth

The name "Earth" is derived from the Old English word "Erda," which means "ground" or "soil." Interestingly, despite this name, which suggests a solid and earthy surface, 71% of the Earth's surface is covered by water.

This vast expanse of water is why Earth is often referred to as the "blue planet." The contrast between the name "Earth" and the reality of its appearance forms an intriguing paradox that reflects the complexities of our home planet.

2. The Weight and Growth of the Earth

The Earth's mass is approximately 5.975×10^24 kilograms—a staggering number that underscores the planet's immense size. However, what is even more fascinating is that the Earth is constantly "gaining weight."

In the universe, there are countless comets, meteorites, and cosmic dust particles, some of which enter the Earth's atmosphere each year and become part of the planet.

Scientists estimate that the Earth absorbs about 100,000 tons of interstellar matter annually, with cosmic dust alone accounting for 23,430 tons. This ongoing accumulation means that the Earth is "getting fatter" bit by bit every year, although the change is imperceptible to us.

3. The Rotation of the Earth and Time

Approximately 620 million years ago, a day on Earth lasted only 21.9 hours. Over time, the Earth's rotation has gradually slowed, resulting in the 24-hour day we experience today. However, this change is incredibly slow, with the Earth's day increasing by just 70 milliseconds every 100 years.

If we wanted the Earth's day to lengthen by a full hour, we would need to wait approximately 100 million years. Although this change might seem insignificant, it illustrates the dynamic and ever-evolving nature of our planet.

4. The Reversal of the Earth's Magnetic Poles

Throughout the Earth's history, there have been numerous magnetic pole reversals, where the north and south magnetic poles swap positions. The most recent magnetic pole reversal occurred around 780,000 years ago.

Some scientists speculate that such reversals could have contributed to the extinction of ancient organisms, although this hypothesis has yet to be fully confirmed. Despite the uncertainty, the Earth's magnetic field remains a critical area of study for scientists, who continue to monitor its changes and potential impacts.

5. Jupiter's Guardian Role

The Earth's survival in the vast and often hostile universe is due in large part to Jupiter. With its immense size, massive mass, and strong gravitational pull, Jupiter acts as a kind of "guardian" for Earth.

Many meteorites that might otherwise strike Earth are instead drawn to Jupiter's gravity, leading them to collide with the gas giant instead. In this way, Jupiter has played a significant role in protecting Earth from frequent and potentially catastrophic meteorite impacts.

6. Plate Tectonics of the Earth

Earth is currently the only planet known to have plate tectonics. The planet's surface is composed of seven large plates that are constantly moving and reshaping the Earth's geological features.

Although these plate movements are slow—about 1 to 10 centimeters per year—they play a vital role in the Earth's carbon cycle. This slow but steady movement helps regulate the Earth's temperature, preventing the planet from overheating and maintaining conditions suitable for life.

7. Water Resources on Earth

Of all the water on Earth, 97% is salt water, leaving only 3% as fresh water. However, of that 3%, a staggering 70% is frozen in the polar ice caps, and most of the remainder is hidden deep underground or within the soil, making it difficult for humans to access.

This stark reality underscores the importance of cherishing and conserving the Earth's limited freshwater resources, as they are essential for sustaining life.

The Earth is our only home, a planet that carries billions of years of evolutionary history and hosts billions of species. As residents of this unique world, we have a responsibility to cherish and protect its fragile ecological environment.

Ensuring that future generations can continue to thrive on this blue planet requires a deep respect for nature and an understanding of the Earth's natural laws. Only by fostering a harmonious coexistence between humanity and nature can we hope to create a sustainable future for all life on Earth.