Lightyear
One sun insults another, whose sad face suggests it knows its light is slower than light should be.
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Free for classrooms, worksheets, slides and other non-commercial use under CC BY-NC 4.0, with credit to Ben Orlin.
Cartoon by Ben Orlin, Math with Bad Drawings. https://cartoons.mathwithbaddrawings.com/2016-12-09-lightyear/ (CC BY-NC 4.0)Transcript
Sun 1: "I'm not saying you're lazy, but your photons take 18 months to travel a lightyear."