Previous studies have indicated that the first “building blocks of life” were brought to Earth through meteorites and comets.
Led by Professor Oliver Trapp from Ludwig Maximilian University Munich (Germany), this groundbreaking study reveals an intriguing alternative scenario, in which extraterrestrial “intruders” also make an appearance, albeit in entirely different roles.
“The Presence of Stable Continental Crust and Liquid Water on Earth 4.4 Billion Years Ago, and the Earliest Signs of Biogenic Carbon Isotopes around 3.8-4.1 Billion Years Ago, Suggests Life Emerged Only 400-700 Million Years after Earth’s Formation,” Sci-News quotes Professor Trapp.
Thus, what is referred to as “prebiotic matter” could have emerged as early as 4.4 billion years ago, on a scorching Earth during the Hadean Eon, the earliest geological period.
They examined all the factors that could promote the so-called life-building reactions, hypothesizing that it originated from lifeless carbon dioxide (CO2) readily available on Earth.
Earth during the Hadean Eon – Image: Simone Marchi & Dan Durda/Southwest Research Institute
But that doesn’t mean we lack extraterrestrial origins, as all Earth’s materials have been scavenged from billions of years of cosmic evolution with numerous generations of dead stars and planets, explosions, and enrichments of chemical constituents that give rise to new star systems.
Furthermore, the transformation of carbon dioxide into life is a lengthy process believed to be facilitated by two factors, one of which is extraterrestrial: iron meteorites and volcanic ash.
They act as catalysts in the conversion of carbon dioxide into hydrocarbon aldehydes and alcohols, under the harsh temperature and pressure conditions of the Hadean Eon.
These compounds then participate in subsequent reactions to form carbohydrates, lipids, sugars, amino acids, DNA, and RNA.
The models created by the research team estimate that the continuous bombardment of meteorites and intense volcanic activity of early Earth contributed to the production of approximately 600,000 tons of prebiotic matter annually.
Combined with the existing components in the atmosphere and the oceans, single-celled life emerged and, after billions of years, gave rise to the multitude of species we see today, including ourselves.
The study was recently published in the journal Scientific Reports.