Saturn's moon Enceladus, covered in snow and ice, resembles a perfectly packed snowball in this image from Nasa's Cassini mission. Earth may have looked similar more than 600 million years ago. Photo: Nasa
What caused ‘snowball Earth’ to melt? Researchers find evidence in China
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Saturn's moon Enceladus, covered in snow and ice, resembles a perfectly packed snowball in this image from Nasa's Cassini mission. Earth may have looked similar more than 600 million years ago. Photo: Nasa
