For the first time, evidence of water has been found in a stony type of asteroid once thought to be bone-dry. Grains of dust from the asteroid Itokawa actually contain a surprising amount of water, two cosmochemists from Arizona State University in Tempe report May 1 in Science Advances.

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For the first time, evidence of water has been found in a stony type of asteroid once thought to be bone-dry. Grains of dust from the asteroid Itokawa actually contain a surprising amount of water, two cosmochemists from Arizona State University in Tempe report May 1 in Science Advances.