Our planet is an oasis of life in an otherwise desolate universe. The Earth's temperature, weather, atmosphere and many other factors are just right to keep us alive. The Earth has one moon. It's name is Luna. To learn about Luna Click Here .
Scientists use the Earth to study all the other planets.
Since no human has ever visited another planet, we have to use what we know about the Earth, and try to guess what the other planets must be like. This is called Comparative Planetology. It may not seam like these two things go together, but they do. Mars protected those who fought for their communities, and stayed home to raise crops for food. If you weighed 70 pounds on the Earth, you would weigh about 27 pounds on Mars.