It's the discharge glow from the Polywell Fusor fusion reactor built by students at Penninsula College, in the US.
Over the summer break of 2007, I came across the following article in an edition of Popular Science: Teen Builds Basement Nuclear Reactor! This article intrigued me. If a teenager in Michigan could build one of these in his parents basement, why couldn't a group of science students build one of these in a classroom?
I started thinking seriously about this idea, and couldn't come up with any negative consequences for this project. Think about it: students do the research, design the reactor, order the parts, put them together, and hopefully achieve fusion. Along the way, they are learning about atomic physics, energy levels, binding energy, types of radiation, safety concerns and remediation, metal fabrication, machining tolerances, operations manuals, vacuum technologies, high voltage electronics, gases, plasmas, arc discharge, cross sections, the list just goes on and on.
The project cost a massive $3,000. No, that's not a misprint: that is three thousand dollars.
Meanwhile, over here in Britain, our students barely know what the fuck an atom is and our government is preparing to spunk £100 billion of our money up the wall on sodding windmills.