Green sunlight

[Huderon]

A question my daughter asked this morning stumped me, and not being exactly brilliant at science, I thought I'd ask it here :-)

If the sun gave out only green light, would the world look green to us ?

[fo3nix]

Well, the world technically wouldn't be here (not as we know it, anyway). The Sun also gives out other forms of radiation on the electromagnetic spectrum (of which visible light is only a small part), giving warmth to our planet.

Assuming everything is still intact, and just that the visible portion of the spectrum is replaced with green light only, then no it likely wouldn't be the same green. The atmosphere of our planet scatters light (why the sky is blue and sunsets are red), so the colour would change hue.

[fo3nix]

(Just to clarify, the second paragraph assumes of course that the other colours still exist in the spectrum and that the Sun only radiates green light!)

[eleanswers]

The sun gives out what we know to be 'White light'. (which is made up of the spectrum (as a rainbow) with red light being the longest of wavelengths and violet being the shortest of wavelengths. Hence why the sky is blue (shorter wavelengths scattered about the atmosphere, red sky at sundown - when the sun is furthest away only the long wavelenths (red) are visible.
The colours of objects we see in daylight are determined by absorbsion and reflection of this 'white light'.

If the sun only ommited 'green light' only (which is the medium wavelength) the colour of objects would be determined by absorbsion & reflection of this green light. This is a medium wavelength and the world would be very, very dark with some objects highlighted in green.

[Space]

the answer is no
because our eyesight is adapted to the light that the sun emits.
So whatever colour the sun emits is the definition of "white" to our eyes.