EARTH (OUR PLANET)

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EARTH (OUR PLANET)

1. Earth (Our Planet)

Earth is the third planet from the Sun and the only known planet that supports life. It has a geoid shape, meaning it is slightly flattened at the poles and bulged at the equator. Earth is about 4.54 billion years old and revolves around the Sun while rotating on its axis. Its atmosphere, water, and suitable temperature make life possible. About 71% of Earth’s surface is covered by water and 29% by land. The planet has one natural satellite, the Moon. Earth’s unique combination of air, water, land, and living organisms forms a dynamic and interconnected environment.

2. Key Facts About Earth

Earth has several important physical characteristics. It is the third planet from the Sun and has a diameter of approximately 12,756 km. Its circumference is about 40,075 km, and its average density is 5.52 g/cm³. Earth rotates once every 23 hours 56 minutes 4 seconds and completes one revolution around the Sun in about 365 days. It is located nearly 149.6 million km from the Sun. The escape velocity of Earth is 11.2 km/s. Earth’s axis is tilted at 23.5°, which causes seasonal changes. These facts help scientists understand Earth’s structure and behavior.

3. Atmosphere (Composition)

The atmosphere is the layer of gases surrounding Earth that supports life and protects living organisms. It is mainly composed of Nitrogen (78%) and Oxygen (21%), while the remaining 1% consists of gases such as Argon, Carbon Dioxide, Neon, and others. Oxygen is essential for respiration, while nitrogen helps maintain ecological balance. The atmosphere regulates temperature, protects Earth from harmful solar radiation, and supports weather and climate systems. Without the atmosphere, life would not be possible. It also acts as a shield against meteoroids, preventing many of them from reaching Earth’s surface.

4. Earth Records

Earth has several remarkable geographical records. Mount Everest, located in the Himalayas, is the highest point on Earth, standing at about 8,849 meters above sea level. The Mariana Trench in the Pacific Ocean contains the Challenger Deep, the deepest known point on Earth. The average global temperature is around 15°C, creating conditions suitable for life. Earth’s average humidity ranges between 30% and 35%. These records help scientists understand the planet’s physical extremes and environmental conditions. They also provide valuable information for geographical studies, climate research, and exploration activities around the world.

5. Internal Structure of Earth