By creating an account, you acknowledge that PBS may share your information with our member stations and our respective service providers, and that you have read and understand the Privacy Policy and Terms of Use.
Become a WCNY member to enjoy
WCNY | Passport
Get extended access to 1600+ episodes, binge watch your favorite shows, and stream anytime - online
or in the PBS app.
Season 8 Episode 4 | 8m 23s
| Video has closed captioning.
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.