Spectators Balcony (Spotters Corner)If you're not a professional pilot but want to discuss issues about the job, this is the best place to loiter. You won't be moved on by 'security' and there'll be plenty of experts to answer any questions.
There is a almost 3000m between the aircraft in the shot provided by DaveReid so 1200m separation and rolling with the inbound at 1 mile seem unlikely.