Compact nuclear fusion reactor is 'very likely to work,' studies suggest

"When I meet God, I am going to ask him two questions: why relativity? And why turbulence? I really believe he will have an answer for the first."

Yep; the key technology that took magnetic confinement fusion from 'ITER will probably work' to 'Maybe we should just go ahead and skip ITER' is rebco tape.

The problem is that all known superconducting materials known will lose their ability to superconduct when exposed to a sufficiently strong magnetic field. The large field strengths induce eddy currents in the material which disrupt the propagation of the cooper pairs in its superconducting mode. The current sufficient to self-induce this field is called the critical current.

Layered rebco tape appears to shield against this effect or otherwise trap the eddy currents in a way that superconductivity is preserved even in the presence of extremely strong fields. The critical current in REBCO tape is enormously higher than in previously known materials or winding configurations.

Obviously the bigger the reactor volume is, the smaller the magnetic field needed to steer and confine the plasma within it can be. So back when they were designing ITER, engineers figured out the strongest magnet they could make, then they designed the reactor to be small enough (lol) that said magnet could still sustain confinement.

However now that we have stronger magnets we can make reactors smaller. This is even something of an gross understatement as the relationship is cubic. For a doubling in field strength, the reactor can be 8 times smaller. That effect is very meaningful when considering that you are essentially talking about shrinking something the size of ITER's 28m main reaction vessel to something that might fit into a garage.

I'm not really any kind of expert on this, so please treat this explanation as very simplistic.

I have not yet personally seen anything about this new lattice confinement modality that seems to give me anywhere near the same level of confidence that they will see viable applications compared to the magnetic confinement approach. (NIF already stood down their tries at laser inertial confinement) Maybe someone has some good insight on whether or not this is all still speculative fanfare or if researchers are finding real meat.

What we really need are better ion propulsion systems. Even with a power source current ion propulsion systems are much slower than chemical rockets for short-term deep space missions like transit to Mars.

https://en.wikipedia.org/wiki/Electrically_powered_spacecraf...

Realistically, if we had good electric propulsion we could just slap a conventional fission reactor in there. We already launch plutonium on many deep-space missions for steady nuclear power. For now chemical propulsion is simply faster and more reliable, electric propulsion is still in the early stages, and there are many other problems to solve in human spaceflight.

Speaking even more pedantically, a new decade is starting right now ... and here comes another one.

The 2020s start 2020-01-01 (just as the century called "the 1900s" started 1900-01-01).

The 21st century started 2001-01-01.

The 203rd decade starts 2021-01-01 -- but nobody talks about the "203rd decade". That's the difference in terminology between decades and centuries; we don't refer to decades by their ordinal numbers.

Yes, it's confusing and inconsistent. If only Dionysius Exiguus had known about zero.

Fusion is relatively easy to achieve. Farnsworth and Hirsch did it back in the 60s and there's a community of people building DIY fusors at home.

The hard part is getting the reaction to produce more energy than it requires to sustain. Given a breakthrough that solves that problem, fusion would be a really appealing energy source given the abundance of hydrogen.