Talk:1441: Turnabout

Explain xkcd: It's 'cause you're dumb.
Revision as of 07:49, 31 October 2014 by (talk)
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In the few seconds the photons take to get to the moon and back, the earth has moved enough on its axis that the reflected beam from a perfect retroreflector is not gonna hit the protagonist.

The retroreflectors for the Apollo missions were deliberately spoiled so they return six slightly offset beams, angled such that photons from one of them will go back near enough to the source.

Oh, and of course there's also the whole r^4 thing too. ‎ (talk) (please sign your comments with ~~~~)

Citation needed. And did you mean the inverse square law? 07:37, 31 October 2014 (UTC)
Since you acknowledge that the reflectors for the Apollo missions were constructed to take this into consideration and the photons will return near enough to the source, the cartoon is still valid.  Now, whether the photons would retain sufficient energy upon their return to cause harm (or why they did not have enough power to destroy the reflector in the first place) is a subject for another discussion . 07:49, 31 October 2014 (UTC)