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

🇺🇸 N17349 - Boeing 737MAX 8 - United Airlines UAL2478/UA2478 (PHX-EWR-SAV) - 4.8 mi away @ 38875 ft, heading E at 555 mph. Spotted 6x before! [05:17:50 PM CDT] #A12758 #N17349 #B38M #UNITED #UAL2478 #UA2478 #ADSB #ADSBbot