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Explain xkcd: It's 'cause you're dumb.
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Whenever I miss a shot with a sci-fi weapon, I say 'Apollo retroreflector' really fast, just in case.
Title text: Whenever I miss a shot with a sci-fi weapon, I say 'Apollo retroreflector' really fast, just in case.


In this comic "they" refer to [1]. A mirror that was placed on the moon by Apollo 11. A special kind of mirror that reflects the light back to where it came from. The mirror is used to measure the distance between earth and the moon.

In this comic "the one to the right" hopes for that the missed laser shot will hit the moon and the laser raging reflector on the moon and then hit his opponent in the back.

A retroreflector is a device or surface that reflects light back at its source. The Apollo 11, 14 and 15 moon missions placed several such devices on the surface of the Moon to help scientists on Earth measure the distance between the two bodies using laser ranging.

In the comic, two people are engaging in a battle with laser guns. One appears to gain the upper hand as he jumps on a desk, as the other's shot goes wide. He delivers the classic line "Any last words?" and is answered with the confusing phrase "Apollo retroreflectors". The earlier wild shot, reflected off the moon, promptly lances down from space and hits him in the back.


Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.

[Two people engage in battle using handheld laser guns.]

[Person 2's shot misses, Person 1 jumps on a desk.]

Person 1: Any last words?

Person 2: "Apollo retroreflectors"

Person 1: What?

[Person 1 is hit in the back by the reflected shot.]

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