Overview

• Researchers led by Yu Xia report in PNAS that charge builds at curved gas–liquid interfaces of rising methane microbubbles, creating brief electrical microdischarges.
• A custom bubble generator and high-speed cameras captured the microblitzes as bubbles merged or burst, providing sufficient energy to ignite methane without an external spark.
• The resulting non-thermal combustion produced cool blue‑violet luminescence matching historical sightings over wetlands and cemeteries.
• Similar microdischarges were observed with other gas mixtures, indicating electrified bubble interfaces are a general natural mechanism that can drive redox reactions.
• Scientists note that some reported lights have other explanations such as fireflies or fungi and that direct field confirmation and prevalence of the mechanism remain open questions.