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 Originally Posted by OngBonga
I'm assuming naked and very very far away from a sun.
There's nothing in space to dissipate heat, so I'm thinking maybe we burn up.
Blackbody radiation dissipates heat. This is how cooling fins work in space.
This is how the ISS keeps its temp regulated. Some of those big panels on it are solar panels, but some of them are BB radiation surfaces.
None of which answers the real questions, here.
How much power is generated by a person's body heat?
How much power can be dissipated via BB radiation from a person's body?
The first is about 100 Watts for a person whom is active, but not working up a sweat. That can go up to about 150 W for a person working out or whatever.
The 2nd is a bit harder to get at. A typical human has about 2 square meters of skin, and is at a temperature of about 300 K.
P = A*{sigma}*T^4
where P is the power emitted by the blackbody (under a whole lot of simplifying assumptions) in Watts, A is the surface area of the blackbody in m^2, {sigma} is the Stefan-Bolzmann constant, 5.67(10)^(-8) W/(m^2*K^4), and T is the temperature in Kelvin.
Plugging that in,
P = {2 m^2} * 5.67(10)^(-8) W/(m^2*K^4) * {300 K}^4
P ~= 920 W
So you're initially emitting 920 W, but only generating as much as 150 W, and you're rapidly cooling.
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