How lightning strikes may have played a role in the formation of life on Earth

LIGHTNING STRIKES occurring over a billion years may have provided sparks of life for the early Earth, according to new research involving a Yorkshire academic.

A new study suggests that, over time, these bolts unlocked the phosphorus necessary for the creation of biomolecules that would be the basis of life on the planet.

Phosphorus is necessary for the formation of life but was not easily accessible on Earth billions of years ago.

For the most part, phosphorus was locked inside insoluble minerals on Earth’s surface.

Scientists have wondered how Earth’s phosphorus got into a usable form to help create DNA, RNA, and other biomolecules needed for life.

Benjamin Hess, a graduate student in Yale’s Department of Earth and Planetary Sciences, said: “This work helps us understand how life may have formed on Earth and how it could still be forming on other, Earth-like planets.”

Researchers first looked at meteorites, with the idea that they contain the phosphorus mineral schreibersite – which is soluble in water – and crashed on Earth’s surface with enough frequency to create the conditions necessary for biological life.

However, the drawback to this theory had to do with frequency.

During the period when life is thought to have begun, anywhere from 3.5bn to 4.5bn years ago, the frequency of meteorite collisions on Earth plummeted. However, there was another source of the phosphorus found in schreibersite.

It can also be found in glasses called fulgurites that form when lightning strikes the ground.

This glass contains some of the phosphorus from surface rock, but in soluble form.

Mr Hess and co-authors Sandra Piazolo and Jason Harvey, from the University of Leeds, estimated early Earth saw one to five billion lightning flashes every year (compared to about 560m flashes per year today).