Phil Hobbs said:
When you say "little IR", what are you comparing it with?
Other blackbody radiators, normalized by peak output.
Blackbody
curves for different temperatures never cross--
As I recall, they do. The sun emits very little microwave radiation, while
the cosmic background temperature gives off copious amounts.
(I suppose it might be possible to place microwave detectors on the sun
(nevermind the physical difficulty of diodes operating at 7000K, but that's
just an engineering problem), collecting the few picowatts of CBR that pass
along, relaying that power back to a cold sink which thereby radiates more
microwave radiation. Likewise, the cold sink transforms the visible
radiation from the detector into additional microwave radiation.
It's an interesting thought, but I'm sure that, if I ran the numbers, I'd
discover that it doesn't come out over unity, which is how it ought to be,
after all.)
heating up an object
makes it glow more brightly at all wavelengths. Thus the Sun is a much
brighter infrared source than any terrestrial object, other than a laser.
Infrared perhaps, but not far IR or microwave.
Consider: if this were true, then celestial x-ray and gamma sources would be
visible on telescopes (assuming there is a direct line of sight, which for
energetic radiation, need not be). Many radio and x-ray sources are only
visible due to visible-spectrum matter, as I recall.
Tim