Backscatter electron image of a lunar melt inclusion from Apollo 17 sample 74220, enclosed within an olivine crystal. The inclusion is 30 μm in diameter. Skeletal crystals within the melt inclusion are a fine mixture of olivine and ilmenite. Dark area in the lower-left is an ion microprobe sputter crater.
Water deep inside Earth and the moon may originate from the same source: ancient meteorites, scientists say.
The findings hint that water may have existed on Earth before the giant impact the planet received that created the moon, and that the moon possessed water from its earliest moments, scientists added. It remains a mystery exactly how water found within the moon survived this violent collision, though.
Water is vital to life as we know it, with organisms found virtually everywhere there is water on Earth. When Earth was born, the ingredients of the planet's water most likely would have formed beyond the orbit of Earth. As such, all the water on the planet must have come from either comets or meteorites hurtling inward from the outer solar system.
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