At the speed of light, the Sun’s glow crosses about 150 million kilometers in roughly eight minutes and twenty seconds — so the sunshine on your skin is already a short trip from the past.
If the Sun vanished instantly (it won’t), Earth would keep orbiting and glowing in “old light” for those same minutes before the dark arrived. Space distances hide inside everyday brightness.
That delay is a gentle intro to cosmic lag. Starlight from farther suns is older still — tonight’s sky is a collage of many different “nows.”
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