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.