Alberto Saal, Brown University (IMAGE) Brown University Caption Water deep inside the moon and water inside the Earth both came from the same source, according to research led by Alberto Saal, a geochemist at Brown University. The moon is thought to have formed after a giant impact to a still-forming Earth 4.5 million years ago. These new findings suggest that the moon's water may have been transplanted from Earth from that impact. Credit Mike Cohea / Brown University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.