Scientists Make a Major Breakthrough in Solving a Hair-Raising Mystery About Static Electricity

The findings can help explain the physics behind phenomena like volcanic lightning

Sara Hashemi

– Daily Correspondent

March 20, 2026 11:29 a.m.

Static electricity may seem simple. Students often learn that rubbing a balloon against their hair will cause negatively charged electrons to jump from the strands to the rubber. Because the different materials now carry opposite charges, with hair being positive, the two items are now attracted to one another.

But many elements of static electricity have remained mysterious to scientists. One puzzling detail is that two objects of the same material can also exchange charges, which theoretically shouldn’t be possible. That’s how bits of ash can rub together and spark lightning above volcanoes and how dust storms might trigger similar zaps on Mars.

Now, new research is shedding light on the long-standing conundrum. Surface contamination with carbon-carrying molecules from the air plays an important role in the phenomenon, according to a study published March 18 in the journal Nature.

This discovery resolves “one of the bigger questions in the field, a scientific mystery that has lasted for decades,” says Justin Burton, a soft matter physicist at Emory University who wasn’t involved in the work, to Rachel Berkowitz at Science.

The researchers examined silica glass, one of the universe’s most abundant solid materials. But to study static electricity, they couldn’t touch their chosen material—with their hands or any other tools—during the experiments since contact would cause electrons to transfer.

So, the team built an apparatus that used sound waves to levitate a glass bead above a plate also made of silica. Turning off the sound would cause the sphere to fall and ricochet off the plate, and the researchers could measure the charge transfer before and after each contact.

Repeatedly bouncing a bead caused charges to build up on the objects, but sometimes the sphere became positively charged, and other times it became negatively charged. However, heating some samples up to about 572 degrees Fahrenheit or hitting them with high-energy gas—to clean the test materials—revealed a pattern of charge flow.

If both the sphere and the plate were treated, they rarely picked up charges in the levitation experiment. Over time, the random pattern re-emerged. But if only one recently cleaned object was used, it always gained a negative charge.

 “At this point, we started contacting other groups that study material surfaces and can precisely measure surface compositions to compare the samples before and after baking,” says study co-author Galien Grosjean, a physicist at Universitat Autònoma de Barcelona in Spain, in a statement. “That’s when we found that subjecting the materials to such treatment stripped them of their natural coating of environmental carbon species.”

Grosjean and his colleagues inspected the materials under a microscope and saw that samples that hadn’t been cleaned were covered in a thin layer of carbon-rich molecules. After a few hours, even the treated materials gained a molecular coating.

“This carbon cake, it just grows on everything, in every environment,” says study co-author Scott Waitukaitis, a physicist at the Institute of Science and Technology Austria, to Emily Conover at Science News.

The work could help explain puzzling phenomena like volcanic lightning and dust storm zaps, as well as the birth of planets. Contact electrification might play a role in how swirling gas and dust around stars stick together to form young planets, Gerhard Wurm, an astrophysicist at the University of Duisburg-Essen in Germany who was not involved in the research, tells Science. The study shows that carbon-based molecules are “important in this story,” he adds.

Waitukaitis agrees. “Some current models of planetary formation rely on a predominant effect of charge,” he says in the statement. “As such, our research might have just shed light on the mechanism underlying the sparks of creation.”