I've read that H2O has an absorption/emission band around to 10 micron range. What conditions are required for photons of this wavelength to be emitted by H20 gas? In particular, how hot would the gas have to be? What amount of pressure is required? Under everyday conditions (like steam possible to detect an appreciable amount of these photons? Also, how would you determine this for any wavelength absorption/emission band? Thanks for any and all responses!