Why do the stars look like there shining blue and red

argosy2006

How come the stars look like there shining blue and red tonight,
celebrating xmas/?
no really go look at them now,
there is one in particular that looks like its multi colored,
explain why please,?

polyfusion

That might be Betelgeuse you're seeing. Loads of info here:

http://en.wikipedia.org/wiki/Betelgeuse

argosy2006

polyfusion wrote: »

That might be Betelgeuse you're seeing. Loads of info here:

http://en.wikipedia.org/wiki/Betelgeuse

its about 13-25 degrees east in sky tonight,
could it be what u speak off,

murphyme

Probably Sirius .

I saw it last night low in the east and it looked like a christmas ornament.

Sirius is often mistaken for planes, UFOs etc..

Michael.

calchas

The colour of stars is directly related to the temperature that they 'burn' at. hotter = bluer, cooler = redder.

Unless we get enough light into our eyes we don't percieve the colour well.

As the star light passes through the atmosphere the light is attenuated and refracted (changing it's coloure as we see it) (the moon low in the sky is yellow orange, but high it is brighter and whiter.

Last night the atmosphere was very dry so the colour was easier to see. Thus compared to usual you saw the colour better.

That's the most likely set of circumstances.

Calchas

Stargate

calchas wrote: »

The colour of stars is directly related to the temperature that they 'burn' at. hotter = bluer, cooler = redder.

Unless we get enough light into our eyes we don't percieve the colour well.

As the star light passes through the atmosphere the light is attenuated and refracted (changing it's coloure as we see it) (the moon low in the sky is yellow orange, but high it is brighter and whiter.

Last night the atmosphere was very dry so the colour was easier to see. Thus compared to usual you saw the colour better.

That's the most likely set of circumstances.

Calchas

When we do get the right conditions Calchas , the night sky is magical , but damp misty foggy nights happen too often in Ireland So yes you are right a dry night is nice !!:cool:

argosy2006

murphyme wrote: »

Probably Sirius .

I saw it last night low in the east and it looked like a christmas ornament.

Sirius is often mistaken for planes, UFOs etc..

Michael.

yes exactly like a christmas ornament, sirius eh, kool, learn something new,

jumpguy

Night air tonight feels moist and abit damp. Beautiful cool night though and a very nice night to go for a late walk. However, when stars twinkle, atmospheric conditions are poor for deep-space viewing. Betelgeuse is probably what you're seeing, very yellowy tonight, abit like Mars.

Stargate

jumpguy wrote: »

Night air tonight feels moist and abit damp. Beautiful cool night though and a very nice night to go for a late walk. However, when stars twinkle, atmospheric conditions are poor for deep-space viewing. Betelgeuse is probably what you're seeing, very yellowy tonight, abit like Mars.

Jumpguy you out walking now lol .>>>> its late , Yip night air very damp and cold here in Cork too , scope would be useless after 20mins in that air .

signal terror

Appearing red or blue can also be attributed to the speed at which the stars are moving and if its to or from us.The Doppler effect.At high enough speeds,stars moving away from us will have their light compressed to a certain wavelength which causes a certain color and vice versa.

RodgerTheDoger

calchas wrote: »

The colour of stars is directly related to the temperature that they 'burn' at. hotter = bluer, cooler = redder.

Unless we get enough light into our eyes we don't percieve the colour well.

As the star light passes through the atmosphere the light is attenuated and refracted (changing it's coloure as we see it) (the moon low in the sky is yellow orange, but high it is brighter and whiter.

Last night the atmosphere was very dry so the colour was easier to see. Thus compared to usual you saw the colour better.

That's the most likely set of circumstances.

Calchas

Just to add to this - Blue light is a lot easier for us to see, we do not visually see red light as easy unless the source is a lot stronger - i.e. The sun appears orange. Our atmostphere looks blue, not because it is blue but simply it is the type of light we see best at out optical range so the other colors are drowned out.

Ostrom

RodgerTheDoger wrote: »

Just to add to this - Blue light is a lot easier for us to see, we do not visually see red light as easy unless the source is a lot stronger - i.e. The sun appears orange. Our atmostphere looks blue, not because it is blue but simply it is the type of light we see best at out optical range so the other colors are drowned out.

The drowning out of different wavelengths is caused by rayleigh scattering, not just your eyes

RodgerTheDoger

efla wrote: »

The drowning out of different wavelengths is caused by rayleigh scattering, not just your eyes

Your statement makes no sense, almost like saying "The sky not blue, the sky is blue"

My explaination why we see blue and not red was in reference to rayleigh scattering. The shorter wavelengths which are blue are more visible to us.
My explaination "Blue light is a lot easier for us to see, we do not visually see red light as easy" may have been somewhat simplistic.

And it has everything to do with your eyes, your eyes are a device that interprets electro magnetic radiation at a particular wave length - If you where able to change the wave lenght say to infrared you perseption of the colors would probably be a lot different.