Ancient Earth froze over in a geologic instant - An analysis of a newly discovered rock sequence in Ethiopia supports a Snowball Earth event some 717 million years ago and suggests it took place in mere thousands of years—the geologic equivalent of a cold snap.

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Ancient Earth froze over in a geologic instant - An analysis of a newly discovered rock sequence in Ethiopia supports a Snowball Earth event some 717 million years ago and suggests it took place in mere thousands of years—the geologic equivalent of a cold snap.