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

🇺🇸 N139SY - Embraer EMB-175 LR - United Express SKW4718/OO4718, Denver (DEN) to Huntsville-Carl T Jones Field (HSV) - 4.3 mi away @ 35675 ft, heading ESE at 565 mph. Spotted 23x before! [08:55:10 PM CST] #A09E47 #N139SY #E75L #SKYWEST #SKW4718 #OO4718 #autopilot #ADSB #ADSBbot