[pmrid (Peter)]

I suppose it's an asteroid. But since I haven't encountered this in an image sequence before I thought it may be a good opportunity to learn something more about them.
I was doing an image sequence on M20 last night (25th June) between about 7.30 and 10.30 taking 10-minute subs in Ha, O3 and SII. I happenied to be scanning some of the Maxim raw subs and thought I detected movement. And sure enough, there it was.
It shows up in the O3 and SII subs but not the Ha - possibly swamped by the intrinsic brightness of Ha. But here are some crops from the O3 and SII subs that I have marked with the time of the subs.
I can only attach 8 JPGs at a time here, it seems, so I'll put the remainder in another message.

I wonder how one goes from here to track down an object sich as this.
Peter