Cold air, really cold air, can do things with light and color that from a visual perspective are quite striking. Frozen water vapor droplets act as billions of little tiny prisms, dust particles clinging to that frozen vapor act as filters, and sometimes you end up with really pretty sunsets as a result.
I don't take a lot of sunset photos, as I think sunrises generally provide better light opportunities than sunsets, but this was an exception I thought worthwhile.
