Water is abundant both on Earth and in our own solar system. Water ice has been detected on the moon, in comets, and the rings of Saturn, among other locations in the solar system. Studies have determined that water played an important role in the early formation of our solar system. To learn more about the role water played, researchers have searched for evidence of liquid water in meteorites.
Researchers have found water as hydroxyl’s and molecules in meteorites in the context of hydrous minerals. A hydrous mineral is essentially a solid with some ionic or molecular water incorporated inside. Scientists have now found liquid water inclusions inside salt crystals located inside a class of meteorites known as chondrites.
Chondrites represent the vast majority of all meteorites that have been found on earth. The researchers have found that the salt inside this type of meteorite originated from other more primitive parent objects. The team wanted to determine if water inclusions present in the meteorites are a form of calcium carbonate known as calcite within a class of meteorites known as carbonaceous chondrites.
The team examined samples of the Sutter’s Mill meteorite, which is a carbonaceous chondrite that originated in an asteroid that formed 4.6 billion years ago. Using advanced microscopy techniques, the team found a calcite crystal containing a nanoscale aqueous fluid inclusion with at least 15 percent carbon dioxide. The finding confirms calcite crystals in ancient carbonaceous chondrites can contain not only liquid water but also carbon dioxide.
Researchers say the presence of liquid water inclusions in the meteorite has implications concerning the origins of the meteorite’s parent asteroid and the early history of the solar system. They believe the inclusions likely occurred due to the parent asteroid forming with bits of frozen water and carbon dioxide inside it. That means the asteroid would’ve formed in a part of the solar system cold enough for water and carbon dioxide to freeze, likely outside of the Earth’s orbit and possibly beyond the orbit of Jupiter.