David Kirtley

And so you see the light emission through that, but also it's very bright.

And so the actual vacuum vessels themselves that we use are ceramic.

There are some versions of silicon and oxygen, typically quartz, but there's also some other centered materials.

And it's so bright that they can shine through those materials.

And so what you see is you see the light of not fusion.

When fusion's happening, thermonuclear fusion is so hot that the light is in the X-ray spectrum.

And the human eye can't see that.

But as you're...

is that ice-cold one million degree plasma.

When you're just getting started, it's emitting photons in a range and light in a range that humans can see.

And so you see that bright purple fuchsia color.

We have high-speed ones and low-speed ones.

The traditional SLR cameras, which are the ones that represent the right color, all they catch is the light, the integrated light, the flash.

They can't see the plasma forming, accelerating, compressing.

They can't see any of those things.

They just see all of it integrated into one bright flash.

But the high-speed cameras...

They can see that.

And so the high-speed cameras we can use to actually measure that.

In fact, we put special filters on them to measure different wavelengths of light.