In a groundbreaking study published in Scientific Reports, researchers have shed new light on the origins of life on Earth. The study proposes that iron-rich particles from meteors and volcanic eruptions played a crucial role in generating the precursor molecules necessary for life to emerge approximately 4.4 billion years ago.
Previous research had suggested that the building blocks of organic molecules could have arrived on Earth through asteroids, comets, or through reactions in the early Earth’s atmosphere and oceans. However, the exact mechanisms responsible for producing these vital precursors remained elusive due to a lack of data.
Led by Oliver Trapp, the team of scientists conducted experiments to investigate whether meteorite or ash particles could have facilitated the conversion of atmospheric carbon dioxide into organic molecule precursors. They simulated conditions believed to have existed on the early Earth by subjecting carbon dioxide gas to various pressures and temperatures while introducing wet and dry climate conditions.
By introducing crushed samples of iron meteorites, stony meteorites, volcanic ash, and relevant minerals found on Earth, the researchers discovered that the iron-rich particles acted as catalysts for the conversion process. Across a range of atmospheric and climate conditions, the particles promoted the formation of hydrocarbons, aldehydes, and alcohols, with aldehydes and alcohols forming at lower temperatures and hydrocarbons at higher temperatures.
This finding is significant because it suggests that as the early Earth’s atmosphere cooled, the production of alcohols and aldehydes may have increased. These compounds could have then participated in subsequent reactions, leading to the formation of essential molecules such as carbohydrates, lipids, sugars, amino acids, DNA, and RNA.
Calculating the reaction rates and considering data from previous research on early Earth conditions, the scientists estimated that this proposed mechanism could have generated up to 600,000 tons of organic precursors annually.
The authors propose that this process, in conjunction with other reactions occurring in the early Earth’s atmosphere and oceans, may have provided the necessary conditions for life to emerge.
This study represents a significant step forward in understanding the origins of life on our planet. By identifying the role of iron-rich particles from meteorites and volcanic eruptions in catalyzing the synthesis of organic precursor molecules, it offers a compelling explanation for the emergence of life on Earth billions of years ago. Further research in this area promises to uncover more about the fascinating journey from inanimate matter to the complex web of life we observe today.