We can fins know what causes will-o’-the-wisps

Bubbles merging in water can spontaneously generate electric sparks powerful enough to ignite methane, which may explain mysterious glimpse known as Will-O’-The-Wisps.

In ants, swamps and ants, people occasionally see mysterious blue-dangerous flashes of light over the water, which has often been associated with ghosts or spirits. A more likely explanation of these will-o’-wisps or Ignis Fatuus is that the flashes come from the combustion of gases, such as methane and phosphin, produced by dilapidated organic substances in the varying water below. But it is unclear what would cause the gases to ignite, with appropriate causes such as static electricity or lightning remains untested.

Now Richard Zare at Stanford University in California and Hans Colleugues has observed spontaneous electrical sparks between bubbles of methane and air in water in the laboratory, which they call microlighting. They say that such events could easily have enough energy to ignite methane gas.

“We continue to discover things about water that, once you understand them, are obvious, but before they seem the complex bisar,” says Zare. “No one thinks about water related to fire. They think water is taking out. They don’t tell you with water, I can get a spark and set something on fire. This is new.”

Zare and his colleagues had already seen water droplets, the size of a grain of salt, building charging and spontaneously creating sparks so that they believed that a similar effect could occur between methane bubbles in water. They used a nozzle to send microbles of methane mixed with air through water and observed where the bubbles would collide using a high -speed camera, as well as a photon count and spectrometer.

As the bubbles rose through the water, they change shape and accumulated charge. Whhen to bubbles met, the difference between them would cause a spark that produced a flash that Zare and his team registered with both the camera and the photon.

They also measured the frequencies of light in flash, and found that they matched the signature of specific compound that was chemically excited. This suggests that the sparks would be powerful enough to trigger the ignition of a gas like methane.

“” “[The Italian physicist Alessandro] Volta speculated first that it was lightning that caused these Ignis Fatuus, and in some sense he was right, but not for the reasons he thought, “Zare says.” It is not lightning in the air that comes from heaven; It’s really from the drops. “

“It clearly looks very interesting,” says Detlef Lohse at the University of Twente in the Netherlands. While not a final interpretation of what causes will-o’-wisps, it is a plausible option and says, and the results are likely to trigger further investigation.