I don't know what's more impressive. The entire experience, or the fact that there is a camera inside the reactor.

Amazing stuff through and through.

Probably a fibre-optic tube. One would think those electromagnets would play holy hell with a CCD.

"You want to put my camcorder inside the box that's so dangerous we can't look into it. " -Primer

Why are we building fusion reactors when there is a giant, natural one already there that gives us all the power we could ever need?

Could be, perhaps that's a safer option as well? (chamber integrity). Traditional Si/SiO CCD's are OK in the presence of high fields though. Modified linescan CCD's with MOS sensors replacing the photodiodes have actually been used as magnetic sensors for high discrimination applications in different fields in physics and chemistry, located at times in high pressure vessels at the focal point of some fairly high fields (12 to 20 T). But I still can't figure out how to use my GoPro. Have fun.

Can you build a solar powered long-distance spacecraft? Or would fusion be better?

Because the Sun doesn't have a convenient plug socket

There are some pesky logistical problems in harnessing even a fraction of the suns output.

It's not that it can't be done but.......we could instead just make our own fun sized suns like these people are trying to do.

Nothing else could really touch the output of a fusion reactor if (when) they finally nail it.

Not that solar cells wouldn't still have their niches, or a stopgap role in the mean time.

A matter of scale, distance & speed. (assuming we are talking about electrically driven engines like ion drives or the proposed EM engine.)

If nothing else, the sun gets weaker the further away you get. Out at the edges of the solar system it's almost negligible.

Given that mass directly effects net thrust & fuel range, smaller craft working in the inner solar system may well be better off sticking with solar over a bulky reactor.

Larger and or longer ranged ships should start to favour fusion reactors and such.

Unless of course they manage to miniaturise the fusion apparatus, or perhaps harness quantum effects like matter/anti-matter. etc. etc.

Surface area to volume ratio also starts to shaft solar power the bigger the ship gets too. The panels would have to get exponentially bigger along with the ship/engines.

I couldn't tell you exactly where, but there will be natural tipping points between the practicality of one over the other.

Edit: The calculation would mostly be the ratio of energy produced to mass of the generating apparatus. The point where a fusion reactor (inc it's fuel) can produce more required power per unit of mass than solar cells (and associated gubbins), is the point where it becomes more efficient for most spacecraft.

Though solar still has a clear advantage where indefinite operational duration is a factor. (fusion requires fuel, albeit in small quantities)