The answer is, we don't know. The name "Earth" is derived from both English and German words, 'eor(th)e/ertha' and 'erde', respectively, which mean ground. But, the handle's creator is unknown. One interesting fact about its name: Earth is the only planet that wasn't named after a Greek or Roman god or goddess. For example, Saturn was named after the Roman god of agriculture, and Jupiter's name comes from the King of the Roman gods.

Follow Life's Little Mysteries on Twitter @llmysteries. We're also on Facebook & Google+.

The Earth truly is a planet of extremes, from ice-cold tundra to steamy rain forests, from ocean trenches to snow-covered peaks.

Earth Quiz: Mysteries of the Blue Marble