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Threadlike streams of "Electric wind"
1998 W. Beaty

While playing with dry ice during the June 1998 Seattle Weird Science meeting, I stumbled across a VERY strange electrostatic effect.

VIDEO: Electric Wind Phenomenon


[GIF: click to download] [GIF: click to download]

Fig. 1 (Left) A rotating chip of dry ice leaves a spiral trail of mist on the water. Several "air threads" from my thumbnail are writing identical squiggles in the mist. (The "threads" are about 12 inches long here.) The metal tray is charged at approx. -5,000 Vdc

If several chips of dry ice are placed in a dark-bottomed tray with 1cm of hot water, a layer of moving white mist covers the water. This is fascinating to watch, especially if several dry ice chips are scattered around the pan. Complicated radial gas flows! The white fog creates images which look like comet gas flows, or the bow-shocks of solar wind between neighboring stars. This isn't the interesting part though.

On a whim I grabbed a high voltage DC power supply (about 10KV), clamped a needle on the negative lead, and was directing ion wind at the fog and blowing it around. Here's the weird part. The thick high-voltage wire swung across the tray for a moment, and there appeared in the mist layer a collection of parallel lines, as if the wire had been spewing a number of narrow "rays" which swept across the mist and cut furrows in it. I found that I could wiggle the wire around and draw an array of identical looping patterns as the tips of some sort of invisible "rays" all made identical motions across the mist layer. I pulled the wire back several inches, and still the furrows would appear. These are Charles Yost's "coherent threadlike streams" mentioned in ELECTRIC SPACECRAFT JOURNAL in 1996, I finally found an easy way to create and observe them!

LIKE LONG, INVISIBLE HAIRS

Brief experimentation showed that the entire wire was sending out these "rays" in all directions, maybe one or two of them per cm of wire. They reach out about 10cm to 15cm and terminate abruptly, and seem to be less than 1mm across. If my wire was a like high-pressure hydralic hose, then any tiny oil leaks would behave in the same way as these "rays". They would shoot out like invisible needles, and would carve furrows in the surface of the fog layer.

I had used the negative power lead, while the positive lead was grounded to the pan. The wire is heavy test-probe leads which are fairly old, and not designed for 10KV (maybe has a bit of insulation leakage.) No obvious cracks though. Some of the "air-stream rays" appeared to originate at the tips of tiny pieces of lint which were clinging to the wire.

[GIF: click to download]

Fig. 2 Not the surface of Jupiter, but the slot made in the flowing CO2 fog by a single "air-thread." The emitter is a human hair 1/4" long, held two feet away. Two other marks are also visible, no doubt made by tiny bits of lint on the cliplead which held the hair. The part of the stripe visible here is about 4 inches in length.


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THINGS TO TRY EVENTUALLY:




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