NASA's Voyager Found a 30k-50k Kelvin "Wall" at the Edge of Solar System

It did, but I still didn't understand it. Sorry, not a physics major. And I understand that heat radiates through empty space. Sounds like it's not actually that hot where voyager is, but instead filled with random particles that are that hot.

You're mixing together temperature and heat transfer. That region is very hot, but it transfers very little heat. It's like getting hit with a blast of hot air when you open the oven. The air is hot enough to harm you, but it can't carry enough heat to actually harm you unless you stay there for a long time.

Except where Voyager is, the "air" is so thin there are like a dozens zeroes on the percentage thinner it is, so the amount of heat it carries is also divided by a similar amount.

Each particle is carrying a huge amount of heat, but it gets hit by very few particles. Earth is the inverse; each particle carries a very moderate amount of heat, but you get hit by a lot of them.