"If they are actually water ice, they may shed light on the planet's past climate. The polar ice caps themselves are made of icy layers that researchers believe were laid down as snow during periodic swings in the planet's tilt – and therefore its climate – every 50,000 years. Plaut says studying the shape and thickness of the layers could reveal more about the nature of these climatic shifts."
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The polar ice caps themselves are made of icy layers that researchers believe were laid down as snow during periodic swings in the planet's tilt – and therefore its climate – every 50,000 years.They can believe whatever they want, but there's nothing to substantiate that belief; whereas impacts on Mars are everywhere in evidence.