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How Mars turned red

How Mars turned red
How Mars turned red This illustration shows how Mars transformed from a grey, water-rich world into the dusty red planet we see today. From left to right, the image traces four key stages in this transformation. First, iron in Martian rocks reacts with water and oxygen, forming rust. That rust is then carried by rivers, lakes, and ancient seas, becoming part of the sedimentary layers. A volcano appears in the scene, representing heat sources that may have melted ice, accelerating the movement of rust into surface water. Over billions of years, these rusted rocks eroded into fine dust. Finally, powerful winds spread that dust across the planet, giving Mars its signature red hue. A rover on the surface symbolizes direct scientific analysis, while a spacecraft in orbit observes the planet from above. ESA