Lightning has managed to save enough phosphorous by striking the Earth to contribute to the emergence of life, according to a study published Tuesday that offers an alternative scenario to that generally accepted.
Phosphorous is an essential part of life as we know it, as it aids in the formation of the basic structures of cells and the double helix of DNA and RNA.
Billions of years ago, most of the phosphorus was sealed in insoluble minerals in the young Earth.
But one of its minerals, shripersite, is highly reactive, and it can deliver phosphorous that is used to form organic molecules.
Since most of the shrewers found on Earth come from meteorites, they have often been linked to the emergence of life. But shripersite has been found in molten glass-like rocks produced by lightning striking some clay-rich soils.
American and British researchers used advanced imaging techniques to analyze the amount of rocks produced by lightning.
They then estimated how much shripersite might have been produced in the ages before life appeared and was seen on Earth about 3.5 billion years ago.
“Lightning on young Earth may have produced a large amount of phosphorous,” Benjamin Hess, lead author of the study and a researcher in the Department of Earth and Planetary Sciences at Yale University, told AFP.
He and colleagues estimated that lightning could produce between 110 and 11,000 kilograms of phosphorous per year, according to the study published in Nature Communications.
Using climate simulations of Earth’s early ages, they concluded that lightning exceeded the meteorite fall in terms of phosphorus inputs about 3.5 billion years ago. An era that corresponds to the emergence of life.
According to Mr. Hess, this does not mean that meteorites did not contribute to the emergence of life, but rather “the more sources, the better.”
He now would like to know if this same lightning could have produced phosphorous on other planets where meteorite falls were rare.
“Meteor fall has decreased over time while lightning production, at least on Earth, has been fairly constant over the ages.”