A chemtrails without aircraft leading it

I notice a chemtrail Approximately 20 25,000 feet above me. headed in the direction from Southwest to northeast. I watched it approximately 15 to 20 seconds from the 1 o’clock position till about 9 o’clock position during that time I saw a quick flash of something silver Metallic. about halfway through sighting It appeared and disappeared in 1 to 2 seconds. But the chemtrails proceeded on. I guess what I’m trying to say is whatever was making the chemtrails was invisible.