Study uncovers why the Red Planet is red

Mars may have taken on its rusty colour when oceans still covered the planet's surface

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The colour of Mars's surface is so iconic that it's often simply referred to as the Red Planet. Now a new study has shown it might have taken on this distinctive hue much earlier in its history than previously thought. Though Mars is now bone dry, it appears the colour developed when the planet was still covered with water.

Mars's red colouration has been known about since ancient times as it is clearly visible from Earth, even to the naked eye.