NOTE: For best results, watch at night in a dark room. Much better that way.
(It was hard getting the exposure right without washing anything out.)
Pictured here is a quart canning jar with a hole drilled in the bottom for an extra electrode. The jar is connected to a little old vacuum pump and a 15kv DC TV flyback coil.
Positive is on the right, negative on the left.
As the vacuum is increased, the colorful patterns change and dance about.
