Meteorites Carried Life-Producing Reactive Phosphorus to Earth 3.5 Billion Years Ago

In a new research led by a team of scientists from the University of South Florida, astrobiologists have traced a key element that produced life on Earth. The study shows that the element was brought by meteorites to the Earth, according to a news release.

The new discovery explains how the reactive phosphorous, an essential component for creating life forms, came to Earth from asteroids some 3.5 billion years ago, and how it helped in creating the earliest forms of life.

For several years, scientists have been trying to unravel the process that supported early forms of life. The new study reveals that reactive phosphorus was produced due to the heavy bombardment of the meteorites. And when it got mixed with water, it could be incorporated into prebiotic molecules. 

Phosphorus from meteorites was delivered in minerals that were not present on the Earth's surface. These minerals decayed in water in order to release phosphorus.  

"Meteorite phosphorus may have been a fuel that provided the energy and phosphorus necessary for the onset of life," Pasek, who studies the chemical composition of space and how it might have contributed to the origins of life, said in a press statement. "If this meteoritic phosphorus is added to simple organic compounds, it can generate phosphorus biomolecules identical to those seen in life today."

To prove their finding, researchers examined the core samples of Earth from West Virginia, Australia, Zimbabwe, Wyoming and Avon Park, Florida.

They predict that reactive phosphorus from meteorites was produced in the form of iron and nickel phosphide mineral schreibersite, which in water released soluble and reactive phosphite. Out of the samples they analyzed, they saw the presence of phosphate in samples taken from the early Archean of Australia.

Apart from this, the natural sources of phosphate include geothermal fluids, lightning, and microbial activity that takes place under anaerobic conditions. But none of these could produce the quantity of phosphate that was required to dissolve in the early Earth's oceans and give rise to life forms.

"The importance of this finding is that it provides the missing ingredient in the origin-of-life recipe: a form of phosphorus that can be readily incorporated into essential biological molecules," said Roger Buick, a co-author of the study, according to HNGN.

This study was published in the new edition of the Proceedings of the National Academies of Sciences.