You've probably played with a plasma ball.
Until now plasmas were found in a vacuum, like solar flares, or contained by strong magnetic fields (called a magnetic bottle).
For the first time, engineers at Caltech have created a stable ring of plasma in open air—essentially capturing lightning in a bottle, but without the bottle.
"We were told by some colleagues this wasn't even possible. But we can create a stable ring and maintain it for as long as we want, no vacuum or magnetic field or anything,"…
The stream of water is an 85-micron-diameter jet blasting from a specially designed nozzle at 9,000 pounds per square inch that strikes the crystal plate with an impact velocity of around 1,000 feet per second. For reference, that's a stream narrower than a human hair moving about as fast as a bullet fired from a handgun.
It turns out that the plasma ring emits distinct radio frequencies. "That's never been seen before. We think it's because of the piezo properties of the materials that we used in our experiments," ...