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The branching pattern inside this Captured Lightning sculpture is technically known as a Lichtenberg Figure, or Electron Tree. It was created by injecting a huge amount of electrical charge deep within clear acrylic (Plexiglas) and then suddenly releasing it to form countless lightning-like internal electrical discharges. The hot discharges leave a permanent record of their passage, creating a "Captured Lightning" figure in a process similar to the way fulgurites are sometimes created within sandy soil during a lightning strike. Lichtenberg Figures are named in honor of Georg Christoph Lichtenberg, the 18th century physicist who first discovered them. Dr. Lichtenberg originally used high voltage discharges from electrostatic machines and finely powdered sulfur and lead oxide to create 2-dimensional figures on the surface of insulating materials.
This modern 3-dimensional specimen was created by bombarding acrylic with high-speed electrons using a high voltage linear accelerator (called a LINAC). The LINAC generates a beam of electrons that have been accelerated to as much as 99.5% the speed of light. When these relativistic electrons slam into the acrylic, they easily penetrate the surface, finally coming to rest about half way through the block. This causes a cloud-like region of excess negative charge, called a "space charge", to form in the center of the acrylic block. Since acrylic is an excellent electrical insulator, the injected electrons become temporarily trapped, and a tremendous electrical charge rapidly builds inside the specimen as the beam injects additional electrons.
The potential of the space charge region grows to over 1.5 million volts. Eventually, in a process similar to natural lightning, the huge electrical stress overcomes the insulating strength of the acrylic, and it suddenly breaks down, rapidly releasing the trapped charge. Sometimes, as shown in the picture below, breakdown is manually initiated by (very carefully!) poking the charged specimen with a sharp object. The trapped electrons suddenly rush out in a powerful surge of electricity carrying many hundreds of amperes of current. The high-current discharge creates a countless brilliant miniature lightning bolts inside the acrylic, accompanied by a powerful bang. And, as with lightning, the branching, self-similar discharges can be described mathematically as a type of fractal. Holding a Captured Lightning sculpture is about as just about as close as you can come to holding a lightning bolt in your hand.
 The interior is charged to about 1.5 million volts before being manually discharged
Although the miniature "electrical storm" rages within the acrylic for less than 150 billionths of a second, the hot discharges create thousands of permanent microscopic tubes and fractures within the acrylic, forming a beautiful and permanent Lichtenberg Figure. Every Lichtenberg Figure is unique. Newer figures may retain an amber color on the side hit by the electron beam. Called solarization, the coloration usually fades with time, while the Captured Lightning figure remains as a permanent feature. The lucky buyer will receive a figure of similar quality as the one pictured below and a one-page explanation about how it was created. Note: The discharge exit point may not always be located in the exact middle of the specimen.
 Similar specimen illuminated by sunlight with black velvet background
 Similar specimen illuminated by our LM2750 rosewood light base Although light base is NOT included, we can provide a base for $36 when purchased
with Lichtenberg Figure. Please contact me to add to your order.
Here is a short video clip of a very large (18" x 18" x 1")
We are offering a limited number of these rare specimens. Our Captured Lightning sculptures are stunning and rare objects of scientific art, and they are only available from us. Very few people have actually seen a Lichtenberg Figure, and far fewer are privileged to own a specimen as beautiful as this. The sculpture literally glows when illuminated on an edge by a bright light source (not included). The internal fractures behave like little mirrors, causing the larger discharge paths to sparkle in almost a crystalline fashion, Even the most delicate hair-like tips of the figure are highlighted.
Our team of experienced physicists are Lichtenberg Figure experts. Stoneridge Engineering offers Lichtenberg Figures that range in size from affordable 2" x 2" x 1/2" squares, gorgeous prisms and cubes with multi-layer discharges, and huge 12" x 16" x 1" museum specimens. See About Me for further information about Lichtenberg Figures, our amazing Shrunken Coins, and the mad scientist at Stoneridge Engineering. Also, please see our other unique Captured Lightning and electromagically shrunken coin offerings.
"A physical experiment which makes a bang is always worth more than a quiet one. Therefore a man cannot strongly enough ask of Heaven: if it wants to let him discover something, may it be something that makes a bang. It will resound into eternity." G. C. Lichtenberg 1742-1799
An ideal item for that amateur scientist, student, or collector on your gift list!
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