Red/Blue Shift Bumper Sticker
APS logo'd "If this sticker is blue, then you are driving too fast" bumper sticker.
Based off the Doppler effect, which causes an increase (or decrease) in the frequency of sound, light, or other waves as the source and observer move toward (or away from) each other (like the increased pitch of a train moving towards you). Hence red objects should become more blue as they move towards you at extremely high speeds. This is known as redshift.
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