That's a nice shot of the horsehead, I like it in portrait framing actually, kinda different.
Yes that reflection is pretty bad and you would not want this happening too often
I had troubles with such ray/reflection but the problem has dissapered since upgrading to the new low reflection Astronomik filters (touch wood) although I haven't tried the horsehead region and this is just about the worst spot in the sky for such blemishes to show up.
MIke