READ THIS: I'm Radiarc.

(Mourning in) Canterlot Castle.
One of these days, I'll have one of these songs featured on Equestria Daily...

This song was inspired by the picture.
I don't know why, but this is what I thought of when I saw that picture.
Sadness.
Perhaps the first day Celestia had to lower the sun and raise the moon on her own...

Download link:
http://www.mediafire.com/?k14yzl56aq49qfa