Why James Webb Space Telescope's Has A Signature Color?
NASA's James Webb Space Telescope has to stay super cool to observe the cosmos. How does it beat the heat? Black paint.
As the agency explained in its new YouTube series "Elements of Webb," the James Webb Space Telescope's radiator is painted black to absorb heat. Just like how black asphalt gets hot in the summertime, objects that are black are generally hotter as they absorb all wavelengths of light and convert it into heat. (Comparatively, white objects reflect light and do not absorb heat.) Webb engineers use this principle to keep the telescope cool.
Webb essentially has two sides, a hot side and a cool side, which are separated by the spacecraft's sun shield. The cool side is where its highly sensitive scientific instruments reside, and sun shield blocks any heat from the sun from reaching those instruments. The cool side "even has a radiator to keep it extra cool," NASA multimedia specialist Sophia Roberts said in the video. That radiator and everything except Webb's bright gold mirrors are black on that side, she explained.
