Astrochemistry: December 2018

The origin of the reservoirs of water on Earth is debated. The Earth's crust may contain at least three times more water than the oceans.

By developing a new method for measuring isotopic ratios of water and carbon dioxide remotely, scientists have found that the water in Saturn's rings and satellites is unexpectedly like water on the Earth, except on Saturn's moon Phoebe, where the water is more unusual than on any other object so far studied in the solar system.