I believe if someone did a spectral analysis of the bright spot, it would either show aircraft aluminum (for contrail - light reflecting off of aircraft skin) or engine exhaust (for missile). Either way, you’d have your answer.
I still think this is the most plausible explanation:
http://www.freerepublic.com/focus/f-news/2631987/posts
“most plausible explanation:”
Indeed.... ;>)