system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why is space black?

Why is space black?
gpt
Color comes from light, light directly from a source or light reflected/scattered off a surface. where there is no source or no surface there is no light. Space is a vacuum so there is no source and there is no surface, so there is no light in space. That makes space black.