In space, radiative heat transfer dominates, and the darker the object, the more it radiates (the greater its emissivity). That’s why manned spacecraft are painted white - it “traps” the most possible heat.
“The blacker the material, the more heat it radiates away. In other words, super-black materials, like the carbon nanotube coating, can be used on devices that remove heat from instruments and radiate it away to deep space. This cools the instruments to lower temperatures, where they are more sensitive to faint signals.”
This is contrary to what I’ve always thought…black materials absorb sunlight and heat up, but they in turn radiate the heat away from objects.
Not necessarily. Light is being converted to a longer wavelength and radiated back out. You need to direct the longer wavelength radiation away from the object being cooled.
IR telescopes become more sensitive when cooled because they see heat. The cooler they are themselves, the less they interfere with the heat being collected from the objective.
although there was no mention of the material absorbing the wavelengths used for radar. so I am not sure how well it would work for stealth. But it seems like it would be an interesting product in the solar energy industry as well. In space black may help with cooling but on earth it helps with heating.