Nerd Sniping

Nerd Sniping

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I first saw this problem on the Google Labs Aptitude Test. A professor and I filled a blackboard without getting anywhere. Have fun.

What If? is now on YouTube!
Check out the first video for the answer to
“What if we aimed the Hubble Telescope at Earth?”
and follow xkcd’s What If? The Video Series channel to be notified about each new video.