Thor DM-21 Agena-B – United States Air Force Family: Thor meters Length: meters Diameter: meters Launch Mass: Low Earth Orbit Capacity: The Thor DM-21 Agena-B was manufactured by United States Air Force with the first launch on . Thor DM-21 Agena-B has 11 successful launches and 6 failed launches with a total of 17 launches. Thor-Agena was a series of orbital launch vehicles. Manufacturer United States Air Force is a Government USA entity that was founded in and is administered by . United States Air Force has 19 successful launches and 12 failed launches with a total of 31 launches.