Mars is known as the Red Planet, because it appears in the sky as an orange-red star. The colour caused the ancient Greeks and Romans to name it after their god of war. Today, thanks to visiting spacecraft, we know that the planet's appearance is due to rust in the Martian rocks.
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Which planet, named after the Roman god of war, is also called 'Red Planet' due to its reddish appearance, caused by iron oxide prevalent on its surface ?