The colors in this Mars photo are painted on. Curiosity's navigation cameras shoot 1-megapixel black and white, so NASA merged two grayscale panoramas and tinted them by hand. Blue for the morning shot, yellow for the afternoon one. The rover cost $2.5 billion and your phone has a better camera. That sounds like a scandal until you trace why. Every chip on Mars has to survive radiation that flips bits in ordinary electronics. Curiosity's brain is a RAD750 processor, a hardened version of the…