[sangnoir]

> But for our goal it’s important to remember, because infrared light does not pass through glass

I thought that was UV?! If that statement is true, how on earth am I able to busk in the heat of the sun behind a glass window, indoors?

[malka]

IF is NOT heat. as a matter of fact, IF is a low energy radiation. So, very few heat.

It is what bodies at low temp (like a human being) radiates the most. Higher energie bodies also radiates higher energy light, such as visible light and UV.

[adrianN]

The sun produces visible light as well.

[panic]

Yes, I think this is a common misconception: infrared light is "heat radiation" in the sense that it's emitted from hot things, but any wavelength of light you absorb (not just IR) will heat you up.

[sangnoir]

> but any wavelength of light you absorb (not just IR) will heat you up

Thanks - this is the bit I was un-/miseducated about. When we were taught about radiation in high school, I suspect my young mind concluded that since infrared and visible light were mutually exclusive on visibility, the same applied to heating. To this day, I thought infrared → heat and heat → infrared.

[AnkhMorporkian]

I just happens that at everyday temperatures familiar to humans, the primary wavelengths emitted are infrared. Heat something enough, and that curve will shift to predominantly visible wavelengths; think about an electric oven.