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Bruce Murray Space Image Library

Early Earth

Early Earth
Early Earth A painting of the early Earth by Gary Raham."Our planet, 3.7 billion years ago, didn’t seem like a world ready to welcome life as we know it. An atmosphere of carbon monoxide, carbon dioxide, and methane, seasoned with hydrogen, sulfur dioxide, and nitrogen, swirled above an ocean rich in iron compounds. The moon, ten times larger in the sky and pocked with craters, loomed above a planet spinning twice as fast as it turns today. Volcanoes lofted ash and sulfuric acid into the air. The sun, though 70% dimmer than it is today, provided abundant energy. A seething core and decaying radioactive elements provided even more. Abundant water facilitated active chemistry. The Earth evolved microscopic life, which would, during the seemingly endless stretches of deep time, transform our celestial rock into the pale blue dot we call home." Gary Raham