The Origin of Earth's Water

[David Entwistle]

You'll possibly have seen a lot of recent press regarding the speculation around the origin of Earth's water. Writing for CosmoSparks, on the Planetary Science Research Discoveries web site, Linda Martel provides a clear and concise summary of the recent work. See here for article.

Water, Carbonaceous Chondrites, and Earth

Besides the water we assume was in the original materials that accreted to form Earth, theory holds that water has since been added to Earth by impacting comets and pieces of asteroids—especially the chemically primitive carbonaceous chondrites.

Along with the water, we know from laboratory studies of extraterrestrial materials that comets and asteroids contain prebiotic organic chemicals and amino acids, which only heightens our interest in them as carriers of the ingredients for life. Sorting out the details of water delivery to Earth as well as the larger issue of the different inventories of water ice in the early Solar System are hot research topics. The answers are relevant to planetary accretion models and also to dynamical models that seek to explain how materials moved and mixed in the early Solar System....