Hi ebeyonder,
I came across this article "Oh, those crazy satellites" in the Sep 2011 edition of Astronomy magazine, and think this might be what your white line is.
A floating corpse. I'm copying and pasting bits and pieces of info from the article:
"The broad category of tumblers consist of deceased satellites, spent rockets, collision fragments, and other such objects.....They appear as "moving stars" sailing across the constellations at a steady pace without a murmur. Because satellites shine with reflected sunlight, they may brighten or fade as the viewing angle between the Sun, the satellite, and your eyes changes during a pass....For instance, if the satellite has a highly reflective component, you may see the "moving star" swell in brightness as sunlight bounces off that surface....Watching a tumbler reminds me of watching the Sun glint off the windshield of a distant boat as it bobs and rocks across a choppy sea."
That streak in your photo resembles the ones in the magazine. Just a thought, I could be wrong. But in any case, if it was indeed a tumbler you captured, guess that was your lucky day (night)!

Elnie