the perspective effect and bendy light effect is always in debate here. bendy light is very much thrown out of the window for many reasons even though many do not accept this. ENaG doesnt talk about bendy light but uses perspective and the atmosphere to explain sunsets. today while watching the clouds oposit the sunset i realised something. now this may of been posted before but i havnt seen this in the time ive been lurking here. here is my evidence that throws some ideas of fet away and may force us to think of new ideas.
fig.1.
the green lines represent the surface of the earth.
the yellow lines represent ligh rays
the grey shapes are clouds
the red lines are horizons
the black circles represent the observer
and finally the blue line represent the direct angle to the sun but the light cant be seen
the picture is showing a cloud being illuminated at sunset after the sun goes below the horizon. the most popular theory is that the atmosphere blocks the suns light getting to the observer and thats why we cant see a 24 hour sun. also the other popular theory for clouds reflecting the light off the bottom when the sun is higher is because the light reflects off the earth then off the cloud to the observer.
i added the rets answer to why the clouds are lit from bellow for comparison.
at first i didnt think it was much of an issue. i thought the suns light will be travelling through a lower density therefore it will travel further. but this will explain this picture:
fig.2.
here the suns light only has to travel high up in the atmosphere until it reaches the cloud then reflects off to the observer. but this is when the observer is between the cloud and the sun.
however in fig.1. the light has to travel a much greater distance than it would if it was taking a direct path AND the suns light is traveling through the atmosphere at a low altitude for a greater distance than any other time of the day. yet the light is still able to travel to the cloud and then reflect off the cloud to the observer.