Star Light
Real stars are made of plasma, the fourth state of matter, and so is this one!* I have been working on sculpting a star in flame-worked borosilicate glass, to be filled with inert gas and lit as a gas discharge sculpture.
One of the best known gases that is used in gas discharge lighting is neon, but argon, krypton, xenon, and even helium can be used. These are the noble gases (also called inert gases), which are not chemically reactive. When ionized, each one has its own characteristic color of light. My stars are filled with xenon gas, which lights with a deep blue color when seen inside a clear, transparent glass form. The reason these stars do not look blue is because I coated the inside of the glass with a yellow phosphor. Certain gases, including xenon, produce UV light, which activates the phosphor coating, so this becomes the dominant color instead of the gas color.
This star is part of my porcelain and glass sculpture that is inspired by folio 73r of the Voynich Manuscript. I wanted to make an 8-pointed star, since it is meant to be a three-dimensional interpretation of this illustration:
Although I made multiple stars since I have been practicing sculpting this shape, only one star will be used in this particular sculpture. (The porcelain pieces are close to being done too, so before too long I’ll be able to show all the parts together as intended.)
The star is lit with a high voltage, high frequency power supply which ionizes the gas that is sealed inside the glass shape. There are many different ways to connect a sculpture to the power supply, and this is the first time I have tried a capacitive technique. Often, a glass shape is constructed with an internal metal electrode and wire that is sealed through the glass wall, but I did not want an electrode that would distract from the star shape or make it difficult for it to fit into the porcelain fixture. Instead, I fired a gold luster onto the outer surface of the glass, around the base of the star. Since the gold luster is electrically conductive, a wire can be taped down on top of it, and even though the wire is on the outside of the glass, the high frequencies used will capacitively couple through the glass wall and light the gas within. Also, touching the outside of the glass, or holding my hand near the glass without touching it, can influence the appearance of the plasma light.
As I included in the video, I also used one of the smaller stars to try an experiment of sealing a very thin wire through one of the points, to make an electrode that was integrated into the design. This was the first time I had tried this kind of glass-to-metal seal and unfortunately it did not work out because I did not seal the glass thoroughly enough around the wire, and when put under vacuum, this star would not hold a vacuum (meaning it had a tiny hole where air could leak in). So I did not end up lighting this one this time, but I would like to further practice this kind of wire seal, since I have some other ideas for it.
I also want this sculpture to have a prominently visible wire, instead of being concealed as is desired in some sculpture designs. This way, the wire will lead from the star, to the mouth of the “critter” below*
*seen here enjoying a moment of freedom on the front steps of the ceramic studio before being incorporated into the sculptural assembly:
I made the critter in porcelain, and it has an opening in the mouth and also on its side, so that the wire can pass through and out the back of the sculptural assembly, making it appear that the star is held in the mouth.
*Thank you to Wayne Strattman for the generous and expert advice about a great many parts of the glass and lighting process.
*I should add, for accuracy’s sake, that real stars are thermal plasmas and the lighted star that I made is a nonthermal electrical plasma. But they are both stars nonetheless!