Why is the sky blue and some other colours too?

our atmosphere nitrogen-oxygen, , sun puts out high-energy gamma-rays low-energy radio waves. take 8 minutes photons (packets of light) reach us... although doesn't matter blue sky.

when do, high-energy gamma-rays pass exosphere, thermosphere, stopped quite ionosphere, @ base of magnetosphere (the field created our magnetic field, deflects x-rays , cosmic rays kill us). ionosphere area atoms have had electrons ripped them ("ionized"), makes them @ absorbing gamma-rays (which kill us, other high-energy rays). incidentally, it's why use bounce radio signals on long distances. gamma-rays gone.

rest of spectrum continues deeper atmosphere, until gets stratosphere, , hits ozone layer. ozone layer ultraviolet (uv) light ionosphere gamma-rays. absorbs them, blunts them, stops them (a neat process, below if want know more).

rest of spectrum continues on. low-energy photons, beginning radio, going infrared, red, orange, yellow, , green blow right through surface, infrared provides heat (ir light = thermal energy), , other light provides visible light. green gone.

what's left? blue, violet, , indigo.

our atmosphere loves blue. particularly blue (475 nm). now, when blue photon strikes atmospheric molecule, 1 of 2 things happen:

(1) molecule , bounce off in random direction. think of setting basketball down fifteen feet away, taking golf ball, throw @ basketball, , try guess way it's going bounce.

(2) absorbed molecule, , instantaneously processed , spit out (re-emitted) in random direction.

awesome. but, bounced or re-emitted photon can't go far until it'll hit molecule, @ point, again either (1) or (2) happen. happens again... again... again until have billions of blue photons bouncing on sky, covering in color blue. tyndall effect, though know rayleigh scattering. tyndall civilian scientist discovered first, rayleigh british lord discovered second -- title goes british lord. know, it's not fair. in case, it's because of scattering on earth can during day, , we'll see exact same blue sky (our eyes might interpret color differently, that's biology matter). @ rate, why on earth can during day , see same blue sky.

now, haven't forgotten indigo , violet photons (did you?). they're being scattered similar blue photons, not because of wavelength.

consider human eye not designed see indigos , violets well, , overall effect see sky blue. long sunlight hitting atmosphere, see blue. when sun goes out @ night - blue goes away.

reds , other colors see @ morning , evening caused same way. if you'll recall how during day longer wavelengths blew right through atmosphere, well, have more distance work (look @ curve of ball, , you'll see how works). blues still being scattered, point on earth has rotated away far enough aren't "where blue is." instead, red/orange/yellow being scattered, in exact same way blues. needed longer landing zone.

why sky appear blue? , other colours too?

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