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

🇺🇸 N6704Z - Boeing 757 232/W - Delta Air Lines DAL406/DL406 (ATL-BZN-ATL) - 4.3 mi away @ 37750 ft, heading WNW at 477 mph. Spotted once before! [03:38:49 PM CST] #A8DEB4 #N6704Z #B752 #DELTA #DAL406 #DL406 #ADSB #ADSBbot