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Science and Nature
Be Smart

Sunlight Is Way Older Than You Think. Here’s Why…

Join Joe Hanson as he explores curiosity and illuminates the science behind… well, everything.

Sunlight Is Way Older Than You Think. Here’s Why…

Season 8 Episode 4 | 8m 23s | CC

If the sun instantly switched off like a light bulb–which can’t happen, by the way–then we wouldn’t know for almost 8 and a half minutes. Light travels at the fastest speed there is, but it still takes almost 500 seconds to get to Earth. But the most amazing thing about the sunlight we see is it’s actually SUPER old. How is that possible? Because of the physics and mathematics of random walks.

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