According to a new study, millions of lightning strikes may have been just what life needed to begin on Earth.
One of the key ingredients needed for life as we know it is phosphorus — and the multitude of lightning strikes that happened when Earth was young 4 billion years ago may have unlocked the necessary amount of phosphorus to create the foundation for life.
Phosphorus is needed in the molecules that form basic cell structures and cell membranes and even make up the phosphate backbone of DNA and RNA, said Benjamin Hess, study author and graduate student at Yale University in The Department of Earth & Planetary Sciences.
But this element was elusive on early Earth, trapped inside minerals.
This artist’s rendition of the early Earth environment shows lightning striking volcanic rocks, releasing phosphorus.
“Most phosphorus on early Earth was trapped in minerals that are essentially insoluble and unreactive, meaning they couldn’t be used to make biomolecules needed for life,” Hess said. “Lightning strikes provide a new mechanism for creating phosphorus in a form that can make important compounds for life.”
The study published Tuesday in the journal Nature Communications.
It has long been thought that meteorites delivered the necessary elements for life to appear on Earth. Meteorites have been known to contain schreibersite, a phosphorus mineral that can be dissolved in water. If enough of them crashed into Earth, that schreibersite could have provided the right amount of phosphorus.
These are pieces of fulgurite analyzed in the study.
However, life began between 3.5 to 4.5 billion years ago, and that’s when fewer meteorites were impacting Earth.
Schreibersite has another source in glasses called fulgurite, otherwise known as the glass that forms when lightning strikes the ground.