Since the Earth was formed over 4.5 billion years ago, it has undergone several transformations that have allowed life to thrive. As humans emerged in all areas of the globe, each civilization formed its own ideas about mother earth. It is no coincidence that the phrase “mother earth” is so widespread today. Several early civilizations saw the earth as a goddess. To the Aztecs, she was Tonantzin, “our mother;” to the Incas, Pachamama; to the Chinese, Hou Tu; and to the Greeks, Gaia. One culture that differed from the others was the Egyptians, who depicted the planet as a male, Geb. Earth has the distinction of being the only planet in our Solar System not named directly after a Roman deity. The word “earth” comes from the eighth century Anglo-Saxon word erda, meaning ground or soil. This word originates from Jörð, the giantess mother of Thor in Norse mythology. In Latin, Jörð’s name is Terra Mater, the Roman goddess of Mother Earth. Today, as science and technology advance, knowledge of our planet is ever-changing. We now know the earth is not a perfect sphere. Melting glaciers push water toward the equator, which is stretched by gravity. The moon’s gravitational pull on the earth is also slowing the planet’s rotation, which increases the length of our days by 1.7 milliseconds every century. The 2013 Global Forever stamp was designed by Greg Breeding using artwork by Italian artist Leonello Calvetti. Calvetti created this dramatic image with satellite images and 3-D computer technology.