Here I am on Hadrian's Wall. You can see the vallum ditch in the distance. Aficionados of A Game of Thrones will notice the need to don the black when on the wall. This caused a problem on a bright sunny day. Dull black is an excellent absorber of infra-red thermal radiation and I was soon heating up. Year 10 please note: black absorbs thermal radiation well; it DOESN'T attract heat. No one's ever accused me of looking attractive in this outfit. I'm pictured holding a flask of coffee. Note that it is a shiny silver. Silver is a very poor emitter of infra-red thermal radiation so this minimises the emission from my coffee keeping it hotter for longer.
So note: colder black objects ABSORB infra-red well and heat up. Hot silver objects EMIT infra-red poorly and stay hotter for longer.
