The Sun and what we see?

[Radman40]

They say the sun is a yellow star yet it emits white light. Why is it that when I look out of the window eveything is not yellow? Is it that are eyes are less sensitive to yellow light compared to other wavelengths?

[MikeWilson]

In short: Our eyes have adapted (evolved) to the environmental light from our sun. We see only a short window of the electro-magnetic spectrum and we perceive yellow as a colour on this spectrum.

Different animals see different wavelengths, some like bees and cats are about the same bandwidth but shifted to the blue and to the red respectively. - Source: Richard Dawkins (can't remember which book!).

Mike

[toml42]

The short answer is sun is white, it emits light of all colours.

However, it looks yellow when you look directly at it because all the bluer light is dispersed out in all directions - hence blue skies this is why it becomes redder at sunset, more light is being dispersed.

The 'total' is still white light, clouds being white is evidence of this.

The longer answer, as mike has mentioned is that our eyes having evolved under the sun have adapted to see it this way.

[JulianO]

It's also true that the Suns surface, being about 6000C has its maximum output in the yellow part of the spectrum. It puts out light in pretty much all wavelengths from gamma rays to radio, but its peak is in the yellow. The peak isn't a sharp peak though - so its not pure yellow, and as others have said the atmosphere scatters some of the wavelengths.

Other stars have different characteristic peaks, so look bluer (hotter) or redder (cooler).

[Macavity]

A little background reading / entertainment:

Why Aren't There Any Green Stars? - NASA Spitzer Space Telescope

A lot of information in a SHORT time? Hehe.

[Radman40]

Thanks for the replies and the reading.