Now we don’t always visually *see* the star moving, but what we do see is the impact of the star being pulled towards and away from us on the *color* of the star.
In the Universe, things that are moving away from us are “redshifted” and things that are moving towards us are “blueshifted”.
This is similar to the Doppler shift you hear in sound when a siren is moving towards/away from you. Things moving *towards* you are compressed, and for light this means it turns blue!
#SpaceTalkTuesday (6/)
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