You constantly radiate heat. The warmer you are, the faster you radiate it away. In space this is the primary way you lose heat.
In your living room you are constantly bombarded by radiated heat from all the objects that surround you, even if they’re just at room temperature, which lessens the effect. In space, not so much.
Someone who knows better might chime in, but as far as I know the trope of rapidly freezing out in space is exaggerated. You would definitely freeze eventually, but perhaps not as dramatically fast as portrayed in The Guardians of The Galaxy for example.
Have you ever looked up at a clear summer night sky? Your face will feel cold. Colder than when looking at the ground. That’s because there’s not as much stuff radiating heat at you up there.
Heat doesn’t work quite like that. In order for heat to transfer efficiently, there has to be “stuff” for it to transfer to. Vacuums are famous for lacking “stuff”.
I just did the maths in another post. It’s surprisingly fast! 10 minutes till you die, under 20 till you freeze. Assuming perfect heat conduction and no increased energy generation from shivering or panicking, which probably won’t make much of a difference.
You constantly radiate heat. The warmer you are, the faster you radiate it away. In space this is the primary way you lose heat.
In your living room you are constantly bombarded by radiated heat from all the objects that surround you, even if they’re just at room temperature, which lessens the effect. In space, not so much.
Someone who knows better might chime in, but as far as I know the trope of rapidly freezing out in space is exaggerated. You would definitely freeze eventually, but perhaps not as dramatically fast as portrayed in The Guardians of The Galaxy for example.
Have you ever looked up at a clear summer night sky? Your face will feel cold. Colder than when looking at the ground. That’s because there’s not as much stuff radiating heat at you up there.
Heat doesn’t work quite like that. In order for heat to transfer efficiently, there has to be “stuff” for it to transfer to. Vacuums are famous for lacking “stuff”.
You’re talking about conduction. I’m talking about radiation.
Sure, but radiation acts extremely slowly in the scenario of a person in the vacuum of space.
Yes it is. But it is the main way by which things cool down in space.
That’s how satellite electronics are cooled down. They have large heat sinks that slowly radiate heat away.
And those heat sinks are large because at the low temperatures involved, radiation is not an efficient way to shed heat.
I thought we were talking about a person in the vacuum of space.
A human body will also eventually freeze in space. The same physics apply. It’s just not going to happen fast.
I just did the maths in another post. It’s surprisingly fast! 10 minutes till you die, under 20 till you freeze. Assuming perfect heat conduction and no increased energy generation from shivering or panicking, which probably won’t make much of a difference.
I presume a person would curl up into a ball to preserve heat which would reduce the effective skin surface area. But that is still quite fast
Infrared
Bonus: Making Infrared Cooling Paint From Grocery Store Items