Fleeting light

I glanced up from what I was doing early this evening and saw THIS dramatic sky filling the window. Immediately I grabbed my camera and went outside to take pictures. I'm not sure whether you're familiar with how fleeting sunlight is, but it changes very quickly and you can easily lose "the shot of the century" (as my dad used to say). Even after only 5 minutes, the sky began to look more like this:

Equally as dramatic, but in a different way. Clearly the sun was much farther below the horizon at this point. Not to be outdone, one of the nearby cows started mooing very loudly and repeatedly. I guess she wanted to make sure I noticed her, too.