I would have assigned "colour" with an analogy from soundwaves: We perceive the same note if the wavelength of a soundwave is doubled or halved (octave). Since we can hear around 11 octaves of sound but see less than one of light, I would have used this artistic license to assign a coulour (this, I thought, was behind your question).


Ad rem: The photos show a spacecraft of gleaming, reflective polished metal.

So, white? (Nice if you want to keep the craft colder than the the temperature of the CMB)

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