|MadSci Network: Earth Sciences|
I asked this of the astronomy folk, but(a) they made a slightly incorrect assumption, and (b) couldn`t quite answer my question. Assume an Earthlike planet with an Earthlike atmosphere (oxygen/nitrogen, in other words). Assume that the primary is a star of spectral type K or M. What colour would the sky be? My guess is that there won`t be enough short wavelength stuff for Rayleigh scattering to make the sky blue, so we`re down to pink from particulates, mostly around the horizon, and fairly dark overhead. Is that correct? If not, what would it look like -and bearing in mind that even a small percentage of a red giants outout is quite a lot of radiation, is the answer different if the primary is a giant rather than a main sequence star?
Re: If the sun were a red star, what colour would the sky be?
Try the links in the MadSci Library for more information on Earth Sciences.