Earth

What is Planet Earth?

Earth is the third planet from the sun and it is the fifth largest in the solar system, it’s size just slightly bigger than the nearby planet, Venus. Earth is the biggest of the terrestrial planets. Our home planet is the only planet in our solar system known to harbor living things. Earth is 150 million km from the sun, sunlight takes 8 minutes to reach Earth. As we know, Earth takes 23.9 hours to complete one rotation. And Earth takes 365.25 days to complete one orbit around the sun, so this had brought a big challenge to our calendar system which counts one year as 365 days. To keep yearly calendars consistent with our orbit around the sun, every four years we add one more days, that day is called leap day, and the years it’s added is called a leap year. Nevertheless, Earth is the only planet that has a single moon, our moon is the brightest and the most familiar object in the night sky. In fact, moon is responsible for stabilizing Earth wobble, which can make climates less variable.

Why Planet Earth is named Earth?

The name Earth is at least 1,000 years old. All of the planets, except for Earth, were named after Greek and Roman gods and goddesses. However, the name Earth is an English/German word, which simply means the ground.