Map of the St. Louis area showing the position and track of the aircraft described in the post.

🇬🇧 G-YMMP - Boeing 777 236ER - British Airways BAW97A/BA97A, London Heathrow (LHR) to George Bush Intcntl/Houston (IAH) - 14.8 mi away @ 40475 ft, heading SSW at 523 mph. Spotted once before! [07:28:23 PM CDT] #4007FB #G_YMMP #B772 #SPEEDBIRD #BAW97A #BA97A #ADSB #ADSBbot