Water may have been a part of our planet's history since the beginning.
My childhood books on geology had dramatic drawings of volcanoes belching steam into the atmosphere of a prehistoric and still-sterile Earth, suggesting that our planet was born with a subcutaneous reserve of water, waiting to be lanced to the surface by accommodating eruptions. As a kid, that sure seemed reasonable. But it's not true.
Alexander and his colleagues analyzed samples from 86 carbonaceous chondrites. These primitive meteorites are thought to
They notes that, according to one estimate, nearly 97 percent of Earth's water can be found in oceans, seas and bays while