True, dlux. We are not warmed by direct radiation from the sun, but from the interaction with the atmosphere. If the sun warmed us directly, the closer we got to it the warmer it would get, but the opposite is true. As we climb a mountain or ascend in an aircraft, the temperature falls as the air gets less dense. Once we get above the limits of the atmosphere, it gets freaking cold -because there is no "friction" of the radiation waves as in the atmosphere.
