system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:How does the vacuum in a thermos prevent heat dissipation/loss, but the same does not work for the sun in space?
gpt
The same DOES work for the sun in space. Heat only gets to us from the sun by radiation, not by convection or conduction as there is nothing to mediate the latter two. In a thermos, as well as the vacuum there is a mirrored surface, which prevents radiation as well. There is no mirror in space.