Primitive Earth had significant differences in its skies that we were unaware of until now

(ORDO NEWS) — To be on Earth almost 4 billion years ago would have been incredibly hot, desperately lonely and very short – because there was no oxygen. Now, according to new research, there would be less lightning than in our time.

This could be relevant to any of the hypotheses suggesting that lightning may have been involved in the origin of the earliest life on our planet. If lightning strikes on the early Earth were less common than previously thought, this would affect the calculations.

To dig deeper, the researchers studied how streamer discharges – the sparks that launch lightning – could form in an atmosphere high in carbon dioxide and molecular nitrogen, which is now thought to have been the atmosphere of primitive Earth.

“In principle, in an atmosphere rich in nitrogen and carbon, stronger electric fields are needed for the discharge to occur,” says physicist Christoph Köhn from the Technical University of Denmark.

Chain reactions of accelerating and colliding electrons, known as electron avalanches, are critical to streamer discharges, and the behavior of electrons varies with atmospheric conditions, hence this recently discovered discrepancy.

To complicate matters, we don’t know exactly what the early Earth’s atmosphere was like. In this case, the scientists used the carbon dioxide and nitrogen hypothesis first proposed in the 1990s by geologist James Casting.

An older proposal by Stanley Miller and Harold Urey, published in the 1950s, suggests that methane and ammonia did indeed dominate the atmosphere during the first billion years of the Earth’s existence.

It was Miller and Urey who first put forward the idea that lightning formed the building blocks of life on Earth through experiments in flasks filled with gas, but in recent years ideas about the composition of the atmosphere of that time have begun to change.

“Our simulations show that discharges in the Miller-Urey mixture occur at lower fields than those in the Casting mixture and partly on present-day Earth, suggesting that discharges in the Old Earth atmosphere may have been more complex than previously thought,” the researchers write in new job.

All this means that the process of producing and creating key prebiotic molecules for life using lightning discharges would have taken longer if the latest ideas about the atmosphere of the early Earth were correct.

The researchers don’t specify how much longer; they have modeled only one of the earliest stages of the lightning formation process, and many unknowns remain. However, they say these variations “could potentially make a big difference” in how frequent lightning strikes were.

There is still a lot of work to be done here, such as expanding the scope of the study to cover the entire process of lightning formation and adding more atmospheric chemistry models. Ultimately, we are still looking for answers to the most important questions.

“If lightning bolts were responsible for the production of prebiotic molecules, it’s important to get a very good theoretical understanding of what happened,” says Keng.

“The big question is still where do all these prebiotic molecules come from?”


Contact us: [email protected]

Our Standards, Terms of Use: Standard Terms And Conditions.