Is it possible for life to exist on Mars? Find out whether this is a question for science or science fiction. Study a map created by a 19th-century astronomer who showed a network of canals — possibly built by intelligent extraterrestrial life — which he believed to exist on Mars. Compare this map with actual photographs taken from NASA spacecraft that show these "canals." How do they compare? What does today's technology prove? As you read about the possibility of life on Mars, note how advances in technology and space exploration have shifted our understanding about the planet from fanciful myth to scientific conclusion. (This interactive is not Mac compatible.)

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