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

🇺🇸 N37547 - Boeing 737MAX 9 - United Airlines UAL3909/UA3909, Washington Dulles (IAD) to Harry Reid (LAS) - 4.6 mi away @ 39875 ft, heading W at 433 mph. Spotted 12x before! [03:21:39 AM CST] #A44962 #N37547 #B39M #UNITED #UAL3909 #UA3909 #ADSB #ADSBbot