#1371: Brightness

XKCD comic, described below.
Transcript

[[The panel is white ink on a black background. A character is staring at the ground.]] Character: Based on this decrease in the star's brightness, I believe it is orbited by at least one planet. Exoplanet astronomers at night

Title text:Recently, some exoplanet astronomers have managed to use careful analysis of reflected light to discover Earth during the day.


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