system
Given the following post, respond as if you're commenting on Reddit:
human
Where does all the heat go?

Ok, here's a simple problem that's been bothering me and which i haven't been able to find an answer for:

Things in the world generate heat. Our bodies, most living things, our computers, factories, cars, etc. So where does all this go? Immediately the answer is "dissipated into the air": but then where? The logical assumption would be "vented into space"... but I don't understand how. Does heat just radiate without a problem into a vacuum? Does the earth act like a pot of water: only holding so much heat/water and then discarding the rest?

Really simple problem but I cannot fathom the answer. Also please try to keep this on top (ie no global warming debate).

Thanks!
gpt
Everything gives off light at a frequency distribution and power proportional to their temperature. This is called *blackbody radiation.* So a room-temperature cricket ball in the intergalactic void would radiate light, mostly in the infrared. Each time the cricket ball emits a photon, its temperature will drop slightly, changing the frequency distribution and power of its emitted radiation. Eventually it will come into thermal equilibrium with the vacuum around it, at around three degrees absolute.

So too does the Earth radiate. On the side facing the sun, of course, the Earth absorbs much more light than it emits, but on the night side, the Earth radiates heat away into space.