Can you create a thermal plasma arc in space? And could that plasma be used to melt lunar regolith?

A viewer asked a great question about using thermal plasma for space manufacturing, lunar construction, and regolith melting. The short answer is: yes, you can make a plasma arc in space — but it is very different from making one on Earth.

On Earth, welding arcs rely on surrounding gas or shielding gas that stays near the electrodes. In space, that gas escapes rapidly into vacuum, so sustaining the arc becomes much more complicated. Microgravity also changes the behavior of molten metal, molten rock, trapped gases, bubbling, and flow.

I also talk about how magnetic fields can control plasma arcs. Since plasma arcs involve moving charged particles, magnetic fields can rotate, steer, stretch, or stabilize the arc. This is one of the ...