If all humans died, when would the last light go out?

From xkcd’s What If?

Get a copy of What If? 2 and Randall’s other books at: https://xkcd.com/books
More serious answers to absurd questions at: https://what-if.xkcd.com/

If every human somehow simply disappeared from the face of the earth, how long would it be before the last artificial light source would go out?

Randall Munroe is the author of the New York Times bestsellers What If? 2, How To, What If?, and Thing Explainer; the science question-and-answer blog What If?; and the popular web comic xkcd (https://xkcd.com). A former NASA roboticist, he left the agency in 2006 to draw comics on the internet full time.

Henry Reich is the creator of MinutePhysics and executive producer of MinuteEarth and MinuteFood and founder of Neptune Studios (the parent company for all three youtube channels).

Narrated by and based on "What If?" by Randall Munroe
Written & Directed by Henry Reich
Illustration and Video Editing by Lizah van der Aart
Illustration and Animation by Ever Salazar
Music & Sound Effects by Know Art Studios

What If? The Video Series is the official adaptation of the What If? books by Randall Munroe and is produced by Neptune Studios LLC.

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