Meteorites May Have Delivered Ammonia to Earth

In a groundbreaking new study, researchers have shown that the earliest traces of ammonia on our planet may have been brought here by meteorites billions of years ago. One of the most important ingredients for life on Earth may therefore have an extraterrestrial origin.

The new conclusions are based on the chemical analysis of a meteorite recovered from the Antarctic, which was found to contain carbon. Inside it, chemists found traces of ammonia.

As such, the experts now believe that the substance was brought here from within the solar system, or maybe even from farther away. The chemical may have hitched a ride on meteorites or comets, which may have delivered it to an early Earth.

The conditions here were fairly different billions of years ago, and ammonia may have then been included in the natural processes that eventually led to the development of the earliest forms of life.

These new results are only the latest in a long string of similar discoveries, which continue to indicate that meteorites and comets may have played a critical role in shaping the way our world looks today.

In a paper published in the latest issue of the esteemed journal Proceedings of the National Academy of Sciences (PNAS), experts at the Arizona State University and their colleagues explain that early life here would have not been able to develop without the presence of ammonia in the environment.

The lead author of the PNAS paper is ASU expert Sandra Pizzarello. She explains that meteors of the kind found in Antarctica, called carbonaceous chondrites, are known for containing large masses of organic materials.

“Given that meteorites and comets have reached the Earth since it formed, it has been proposed that the exogenous influx from these bodies provided the organic inventories necessary for the emergence of life,” the ASU group writes in the paper.

Upon impact with Earth's surface, the space rock may have emitted NH4 (ammonia), a chemical that is a critical component in such structures as amino-acids (the building blocks of proteins) and DNA, Universe Today reports.

“The findings appear to trace […] meteorites’ origin to cosmochemical regimes where ammonia was pervasive, and we speculate that their delivery to the early Earth could have fostered prebiotic molecular evolution,” the study authors write.