Water has been found in the dust of an asteroid thought to be bone-dry

Space rocks of this type might have helped create Earth’s oceans

Asteroid Itokawa

PEANUT IN THE SKY  Asteroid Itokawa (shown in this image from Japan’s Hayabusa spacecraft) was thought to be devoid of water. But scientists studying grains of dust returned by the craft in 2010 found trace amounts of the substance.

JPL-NASA

For the first time, evidence of water has been found in a stony type of asteroid once thought to be bone-dry.