As The Tesla car and Starman continue to orbit the earth, How does the paint on the car survive the extremes of temperature? As I understand it, they are both exposed to temperatures between 120C and -100C.
The car will be heated to both the extremes. The side facing the sun directly could have scorching temperatures over 130 celcius while the rear side not receiving any sun could get as cold as -173 celsius. This will result in uneven expansion and contraction of the metallic body and the paint will undoubtedly flake of and cause serious damage to the internals.
The roadster, starman, tires, plastics, seats and other parts will be degraded by the radiations and the paint on the body will also fade for the same reason. Micrometeors may hit the car and dent it as well. Though it is predicted to remain in orbit for millions of years, it will probably disintegrate due to the suns strong radiations long before that.