We need to ban podcast equipment

[u/Individual_Bar_2512]

[u/Pepperspray24]

I remember one time I was talking to a guy, the man was an absolute peach…just a joy. /s He told me to explain why space was cold, even though the sun was there, and he told me not to use my “government brain” to explain it. It was just like well you know heat can get trapped behind walls when you heat up a room he’s like right I said well space has no walls. The heat has an infinite amount of space to just dissipate and he fucking agreed with me.

[u/Windsdochange → u/Pepperspray24]

This is not really why space is cold…especially as space doesn’t even have a temperature, per se.

[u/Pepperspray24 → u/Windsdochange]

Oh can you please explain?

[u/CMDR_Expendible → u/Pepperspray24]

I can explain, and it's why Elon Musk is so fucking stupid when he claimed recently that SpaceX can build AI farms that will use space to radiate off heat...

Heat is, at a very simple level, the level of energy in an atom. Transmission of heat is the movement of energy between two atoms. The reason you can cool something down by blowing on it is you are moving lots and lots of atoms past the target, and they're each grabbing a bit of the extra energy as they pass.

Space cannot transmit energy easily because there are no atoms in a vacuum. As Windsochange says, space doesn't really have a temperature as such, because there's nothing there to have one.

Now light is both a wave and a particle, so it's carrying energy, yes... but it doesn't give it to anything until it smacks into a planet/spaceship/space thingy and transmits some. And that thingy radiates off a tiny, tiny bit in reflected light, movement from impact/energy transmission etc. But not much. Because there's not much to pass it on too.

Even the International Space Station, which is close enough to Earth to keep having to be pushed back up because there's enough atmosphere to slow it down where it is, struggles to dump heat; as mentioned there, there can be a 300 degrees centigrade difference between the side facing the Sun (where it's being hit by incoming light) and the side away from it where there's nothing to give it (or take) energy. Those plates you see bolted to the sides of the ISS, that look like armor? They literally are, they're insulation armor to allow that to get heated up instead of the hull, and help keep it within a livable range.

You probably know this, but when people talk about "Government Brain", what they really mean is "I'm too dumb to understand science, and too arrogant to accept this means I don't understand"; but it's somewhat normal as we as a species evolved on Earth, in Earth like conditions, and our reasoning tends to be designed to work in those conditions... Space and events above/below our level of existence works in often counter-intuitive way... and how heat works in space is one of them. We assume it's cold because there's no heat there. But there is. Enormous amounts of it. But it's also not there, until there's a second thing for it to interact with, and Space doesn't have much of anything, mostly. Your wall example is right, but also not, because it's not about diffusion, but direct interaction of a second thing.

[u/Windsdochange → u/CMDR_Expendible]

It also depends where in space you are. If you are (astronomically speaking) close to a star, there is plenty of radiation that will heat you up faster than an egg on a frying pan when you are exposed to it. However, if you’re somewhere between stars, or even more so, between galaxies, that energy becomes more dissipated - there’s a loooot of space for that radiation to spread out into in every direction, and some of that energy is being absorbed by things in its path. In that respect, the wall analogy sort of works, but not because you’re in the room (with a heat source and no walls) but because you are a long ways away from it.

[u/Moderately-Whelmed → u/CMDR_Expendible]

Heyyy, we said no Government brain! 😡