Solving the Mystery of Pluto’s Giant Blades of Ice: the structures are made almost entirely of methane ice, and likely formed as a specific kind of erosion wore away their surfaces, leaving dramatic crests and sharp divides, as reported in journal Icarus.

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Solving the Mystery of Pluto’s Giant Blades of Ice: the structures are made almost entirely of methane ice, and likely formed as a specific kind of erosion wore away their surfaces, leaving dramatic crests and sharp divides, as reported in journal Icarus.