Welcome to my blog. In this blog, you'll learn about earth and guideline how to protect our earth as your friend.
Earth is the only planet whose English name does not derive from Greek/Roman mythology. The name derives from Old English and Germanic. There are, of course, hundreds of other names for the planet in other language.It was not until the time of Copernicus (the sixteenth century) that it was understood that the Earth is just another planet.
Earth, of course, can be studied without the aid of spacecraft. Nevertheless it was not until the twentieth century that we had maps of the entire planet. Pictures of the planet taken from space are of considerable importance; for example, they are an enormous help in weather prediction and especially in tracking and predicting hurricanes. And they are extraordinarily beautiful.
The Earth is divided into several layers which have distinct chemical and seismic properties (depths in km):
0- 40 Crust40- 400 Upper mantle400- 650 Transition region650-2700 Lower mantle2700-2890 D'' layer2890-5150 Outer core5150-6378 Inner core
