Meteorite findings shed light on origin of Earth's volatile elements

Material from the outer solar system is thought to have been an important source of volatile elements during the creation of the Earth.

Understanding the evolution of our planet is dependent on knowing the origin of the volatile elements. The study, carried out by researchers in the University's School of Earth and Environmental Sciences, in collaboration with workers at theInstitut de Physique du globe de Paris, shows that there is a difference in the composition of meteorites.

The most volatile element in which such unique isotopic signatures have been detected in meteorites is zinc. Earth's zinc inventory is a mixture of both inner and outer solar system material. This shows that the two reservoirs are important sources of Earth'svolatile element inventory.

The part of the solar system beyond the snow line where the giant planets are dominated by gases and volatiles is where the Earth must have come from.

meteorites, as well as being fascinating and beautiful extra-terrestrial objects, are important scientific samples because their chemistries reflect the earliest solids that formed in our solar system. The compositions of meteorites can be used to tell us about the processes and timescales of planet formation as well as give us insights into the types and sources of materials that formed our own planet.

Is it possible that Earth received its volatile elements from somewhere? Did Earth get all of its volatile elements from the outer solar system or is the hotter inner solar system still an important source?

Even though only a small portion of Earth's total mass can come from the outer solar system, this material needs to be volatile-enriched to deliver a third of Earth's total zinc budget. The outer solar system material was enriched with elements more volatile than zinc, and therefore this was an even more significant source of volatile elements on Earth.

New insights into how and from where planets accrete the sorts of elements that are crucial to supporting life--but more broadly, it gives us more clues as to how our early solar system behaved." If newly discovered exoplanets have elements that can support life, we can apply these findings to understand how other planetary systems act.

Further constraints on the transport and delivery of moderately volatile elements can be placed on other bodies in the solar system from which we have samples, such as the moon and Mars. These variations can be used to figure out how stellar environments created these elements and injected them into the pre-solar nebula.

More information: Paul S. Savage et al, Zinc isotope anomalies in primitive meteorites identify the outer solar system as an important source of Earth's volatile inventory, Icarus (2022). DOI: 10.1016/j.icarus.2022.115172 Journal information: Icarus