Comets May Have Transported Noble Gases To Earth: Study

Scientists have surmised that earlier, the earth's water was brought here by asteroids. However, other chemicals and materials, such as noble gases, seem to have been brought here by comets, says a new study.

Noble gases tend to act as repellants to chemical reactions. Hence, they are abundantly present in the atmosphere, but their compositions are a mystery.

In August 2014, the Rosetta spacecraft arrived at comet 67P/Churyumov-Gerasimenko. Hence, experts could get a glimpse into the composition of argon in a cometary atmosphere. This seemed to indicate that comets are a large source of the element.

Thus, even though argon is not important in everyday life on earth, its presence on comets shows that other prebiotic materials also originated from them and can help experts to assess materials such amino acids. The amount of amino acids that was brought to the earth by comets might be the total mass found in all the planet's organisms, even though computation is in its embryonic phases.

"I think it's an interesting exercise," said  Conel Alexander, a planetary scientist at the Carnegie Institution for Science who did not participate in the study. "But it's full of so many uncertainties. My worries are that we still know so little about comet composition."

However, the amount of argon calculated was based on its presence in just one comet. The variability in the concentrations of cometary chemicals and materials too might be very different in various comets.

Even though the experts have yet to arrive at a timeline for the arrival of comets, the new study shows how events leading to the formation of our solar system as well as research will reveal the accuracy of these findings.

The study was published online in the March 9, 2016 issue of ScienceDirect.