Why are things blue shifted and not violet shifted?

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Entropee

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If objects are moving away from us, they are known as red shifted, so why are objects moving towards us blue shifted and not violet shifted?
 
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Semantics. Blue-shifted objects are not necessarily blue: an object emitting at 5 um moving towards us is still blue shifted even though it is way outside the visible spectrum.
 

mathman

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If objects are moving away from us, they are known as red shifted, so why are objects moving towards us blue shifted and not violet shifted?
"blue" and "red" are just labels used to denote upshift or downshift in frequency.
 

Entropee

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Oh ok, yeah I just thought it was odd since most elemtary school students even know that purple comes after blue using roygbiv. Thanks :]
 
If objects are moving away from us, they are known as red shifted, so why are objects moving towards us blue shifted and not violet shifted?
I didn't know that.

So acceleration of the object in relation to us alter wave length?

:eek:
 

ideasrule

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Oh ok, yeah I just thought it was odd since most elemtary school students even know that purple comes after blue using roygbiv. Thanks :]
Actually, purple is not the same as violet. Violet is a spectral color consisting of wavelengths shorter than blue, but purple is a perceptual color seen only when both blue and red wavelengths are present.
 

Entropee

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Oh lol, my bad, I guess it's time for me to go back to Elementary school?
 
What? Entropee said nothing of the kind.
But what he said is right?

I wanna know why!

Edit: Ok so I guess I just got pretty inventive with lack of clear information. LOL
 
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