The question that has tormented generations of scientists may have a surprisingly simple and elegant answer: It wasn't a single, dramatic lightning bolt that gave rise to life on Earth, but billions of tiny electrical discharges between droplets of atomized water. A new study has found that when water is sprayed into the air — from ocean waves, waterfalls, or rain — it naturally creates micro lightning between the droplets.
These tiny electrical discharges, invisible to the naked eye but captured by high-speed cameras, generate exactly the same organic molecules that were thought to require much more dramatic conditions to form. A mechanism so common and pervasive that it finally makes plausible the hypothesis that life emerged spontaneously from the chemical conditions of the primordial Earth. Microlightning could be the missing key that connects the inorganic world to the organic one, the bridge between inanimate matter and life.
Frankenstein's Dilemma and the Electricity of Life
The popular image of Dr. Frankenstein animating his creature with a powerful lightning bolt may contain a grain of truth, but on a much smaller scale. Researchers at Stanford University suggest that it doesn't take giant lightning bolts to create the molecules of life, just tiny electrical discharges that form naturally between water droplets.
The idea that electricity played a role in the genesis of life is not new. The famous Miller-Urey experiment of 1952 he proved that Electrical discharges in an environment simulating the primordial atmosphere could produce amino acids and other essential organic molecules. But there were problems with this theory: if the reactions occurred in the oceans, the molecules created would be too diluted; if they occurred in small ponds, the likelihood of lightning in such a confined space was remote.
The Stanford study solves this dilemma: the micro lightning between water droplets represent a much more common and constant source of electrical energy, which could have triggered the chemistry prebiotics on a large scale.
How Microlightning Works
To test this hypothesis, the researchers conducted an updated version of the Miller-Urey experiment. They filled a container with gases that mimicked the primordial atmosphere (nitrogen, methane, carbon dioxide, and ammonia) and sprayed it with droplets of room-temperature water.
Looking closely, they discovered that The larger droplets tended to become positively charged, while the smaller ones acquired a negative charge. When drops with opposite charges come close together, tiny electric arcs are created between them: the micro lightning.
Since lightning is an intermittent and unpredictable phenomenon, while water splashes are so common on Earth, we suggest that our results provide another possible route for the abiotic formation of carbon-nitrogen bonds.
This is the conclusion that the researchers reached, highlighting how this mechanism could have operated on a global scale and in a continuous manner.
The birth of “biological bricks”
The most surprising aspect of the research published on Science Advances (that I link to you here) is that these microlightnings are sufficient to ionize the air and trigger the formation of organic molecules with carbon-nitrogen bonds, such as hydrogen cyanide, glycine, and uracil. These bonds are among the most common in organic chemistry, and the molecules in which they appear provide the basic building blocks of proteins and DNA.
The process explains how waves, waterfalls and other splashes of water could have produced enormous quantities of organic compounds across the planet, creating ideal conditions for the emergence of the first forms of life.
The discovery of microlightning as a potential driver of early life offers an elegant explanation for one of the greatest scientific mysteries. Not a single spectacular event, but a constant, widespread, daily process may have gradually transformed our planet from a barren place to a cradle of life.
A small spark, multiplied by billions, that changed the destiny of the Earth forever.
