Sunshine - just another point of view

In the core of Sun, there are fusion reactions - these produce photons of very small wavelengths and these go through entire Sun, colliding with other particles there and gradually losing their energy. Thus in the core, there's temperature around 1.36 E7, but on the surface, it's just around 6000K. From there it radiates the light we come to see here on Earth. It's radiation follows the black body model more or less.

But now, this is just above the atmosphere. In the space between Earth and Sun, there's little matter to absorb and reemit the photons, yet in the atmosphere, there's much more. So, we "lose" some (let's face it, quite a lot) of the energy because of reflection and absorption. It's a pity for solar cells and so, on the other hand, we get rid of some not very healthy UV rays - some in Chile might envy this.
Most of the sunshine lost in atmosphere is due to water vapor, CO2 and ozone.

Just by the way - see how human eyes are "equipped" to deal with the most abundant part of spectrum? Beautiful :-)
Consider our eventual color perception, had Sun radiates differently - Sun having surface temperature at 3000K, our color perception would be shifted "red-wards" (and vice-versa)?