Why Do Stars Appear Blue to the Naked Eye but Red in Scientific Images?

AI Thread Summary
Stars appear blue to the naked eye due to atmospheric scattering, while scientific images often depict them as red due to redshift effects. Redshift cannot be perceived without specialized equipment, as local redshifts are too small to detect and cosmological redshifts involve distant objects. The misconception that stars are always red in scientific images is clarified, emphasizing that this is not universally true. Understanding redshift requires knowledge of local and cosmological contexts. The discussion highlights the limitations of human perception in astronomy.
elbeasto
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When I look at the stars in the sky with my undressed eye, they are blue. But pictures of stars taken by scientist always show them as red.

Does this mean that the stars in our galaxy are fairly stationary and/or moving closer to earth? Will I find that most red shifts will be seen in stars that are in other galaxies? Or does this mean I need some expensive tool to see the red shift?
 
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elbeasto said:
When I look at the stars in the sky with my undressed eye, they are blue. But pictures of stars taken by scientist always show them as red.
Always? Where did you get that idea?
elbeasto said:
Does this mean that the stars in our galaxy are fairly stationary and/or moving closer to earth? Will I find that most red shifts will be seen in stars that are in other galaxies? Or does this mean I need some expensive tool to see the red shift?
There is local and cosmological redshift - http://en.wikipedia.org/wiki/Redshift"
The short answer is that you can't perceive redshift with the unaided eye. Local reshifts are too small to differentiate and the objects affected by cosmological redshifts are too far to see.
 
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Borg said:
Always? Where did you get that idea?

You are right. They are not 'always' red. I was making a statement more casual and generic than I should.

Borg said:
... you can't perceive redshift with the unaided eye. Local reshifts are too small to differentiate and the objects affected by cosmological redshifts are too far to see.
Cool thanks.
 
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