Flight Hartsfield Jackson International Airport departs from Atlanta Hartsfield Jackson International Airport at 17:29 and arrives at Houston George Bush Intercontinental Airport at 18:50.
The flighttime is about 2h 21m. The distance travelled ("as the bird flies"): 1213 Km. So the average speed is roughly 516 Km.
There is an 1 hour time difference between Atlanta and Houston