[InterceptPoint]

Here is my Photoshop enhanced version. You can see the trail going from the upper left corner down towards the image of the sun.

[Lonesome in Massachussets]

Interesting. The trail seems to disappear behind the horizon, it doesn't appear in front of the water. It does not quite line up with the "flash" either (try a ruler.) Could simply be a contrail in the distance and glint of the setting sun on the water.

I could sooner believe...