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Mars, the fourth planet from the Sun, was named for the Roman god of war. It is a barren, desolate, crater-covered world prone to frequent, violent dust storms. It has little oxygen, no liquid water, and ultraviolet radiation that would kill any known life-form. Temperatures range from about 80°F (27°C) at midday to about −100°F (−73°C) at midnight. Because of its striking red appearance in the sky, Mars is known as the "red planet." Mars is roughly 140 million miles (225 million kilometers) away from the Sun....
