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

🇺🇸 N818HR - Embraer Legacy 600 - Corporate N818HR - 4.7 mi away @ 39900 ft, heading SE at 502 mph. Spotted for first time! [12:43:06 PM CDT] #AB27D3 #N818HR #E35L #N818HR #ADSB #ADSBbot