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xkcd #2865: The Wrong Stuff
(imgs.xkcd.com)
Alt text:
The phantom found Edward Everett Hale a century too early; by the time we invented satellites, the specifics of his 'brick moon' proposal were dismissed as science fiction.
I love the variety of places explainxkcd editors find to slip in a "citation needed".
You can find those in the what if series too.
“Outer space is a lot higher up than Niagara Falls,[citation needed] so the plunge down into the atmosphere at the bottom of Earth's gravity well adds a lot more than 0.1 degrees worth of heat.”
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