Lichtenberg figures are fern-like branching structures formed from an electrical discharge on or inside of an insulator. Like snowflakes, every Lichtenberg figure is unique – an intricate and beautiful natural work of art. Lichtenberg figures form naturally, sometimes in the skin of lightning strike victims, in lightning strikes into sand (fulgurites), and potentially from pretty much any high-voltage electrical discharge into an insulator. The structures take their name from Georg Christoph Lichtenberg, the physicist who discovered and studied them.
Make Lichtenberg Figures the Original Way
One way to make your own Lichtenberg figure is to use Lichtenberg’s original method. He used hardened tree sap resin for the insulator and dust to reveal the fractal pattern. You can use polyethylene sheets for the insulator and then talcum powder, powdered sulfur, or lycopodium powder to reveal the fractal pattern.
- Place a sharp metal point in the center of the sheet of plastic. A nail is a good choice. All that really matters is that it’s a good electrical conductor.
- Zap the metal object with static electricity. Electricity travels through the metal and across the plastic insulator. The amount of discharge affects how far the pattern extends from the metal point and how deep into the plastic it gets. So, if you shock the metal with your fingertip after shuffling through carpeting, you probably won’t get as big a pattern as if you use a Wimhurst machine.
- Blow powder over the surface of the plastic sheet. It will stick to the pattern, revealing the figure.
Burning a Lichtenberg Figure Into Wood
Another easy method wood-burning a fractal pattern into pine. This can be achieved by applying 2-10 kV of voltage to a pair of nails which have been driven into a piece of dampened pine wood. Another option is to snap alligator clips onto pieces of wood. The reason the pine is dampened is so it doesn’t burn as you apply the electricity. You can mix some baking soda into the water used to dampen the wood to enhance its surface conductivity. You’ll need to experiment with the distance between the nails and the duration of the charge. If the wood starts to dry out, turn off the power and spritz the wood with more water before continuing. A little fire is to be expected and is fine. The type of wood you use makes a difference, too. Here’s what to expect:
There is an easier method you may wish to try:
Acrylic and Toner Lichtenberg Figures
- sharp metal object (e.g., awl)
- insulator (e.g., sheet of acrylic)
- photocopier toner
An adaptation of Lichtenberg’s original method is to use hard acrylic and toner. Gather your materials and make the Lichtenberg figure:
- Position the metal object so that only its tip is touching the surface of the insulator.
- If you have a Wimshurst machine or Van de Graaff generator handy, discharge it through the metal point into the acrylic.
- If you don’t have a machine, you’ll have to generate static electricity another way, like by dragging your feet through a shag carpet and zapping yourself on the metal object.
- In either case, you will create a Lichtenberg figure across the surface of the acrylic, radiating outward from the metal point. However, you probably won’t be able to see it. If you (carefully) blow toner powder across the surface of the acrylic, the Lichtenberg figure will be revealed.
Another way to reveal the fractal is to illuminate it with a light source. You want a strong beam of light and may need to play with the angle to catch the figure. No two Lichtenberg figures are identical, so you will get different results each time you try the project.
When you’re ready to get serious, here’s what you can do…