Scientists from Harvard University have found that lightning striking the ground from the clouds could have played a key role in creating chemical compounds necessary for life on the early Earth.
A group of chemists from Harvard conducted an experiment that simulated conditions on our planet billions of years ago. The scientists created a laboratory biosphere that recreated the original air, water, and land. In this artificial environment, the researchers simulated lightning strikes and analyzed the products of chemical reactions.
The results showed that under the influence of the simulated discharges, carbon was converted into carbon monoxide and formic acid, and nitrogen was converted into nitrite, nitrate, and ammonium. These compounds could have become the basis for the further formation of more complex organic molecules necessary for the origin of life.
The scientists also conducted additional experiments by adding minerals to their virtual environment that were similar to those present in the rocks of the early Earth. After re-simulating lightning strikes, they found the formation of sulfide minerals similar to those found near volcanic eruptions. In addition, the researchers found an increased formation of ammonia, which is considered critical for the emergence of life.
According to the Harvard chemists, their findings suggest that lightning strikes from clouds to the ground were a more likely source of the «building blocks» of life than comets, asteroids, or intercloud lightning.
Life on Earth originated approximately 3.7 billion years ago, but the molecular mechanisms of its origin are still largely unknown. Scientists have proposed numerous theories to explain the origin of life, among which two stand out: primary broth theory and The hypothesis of the RNA world.
Both of these theories take a linear approach, trying to identify a single molecule or class of molecules that contributed to the development of life on Earth. However, the main problem with such linear thinking is the uncertainty about which molecule or class of molecules appeared first.
The complex chemical networks that support life could hardly have arisen from a few extremely complex molecules.
Research, published in the journal Proceedings of the National Academy of Sciences.
Source: Interestingengineering