The Thor-able consisted of the basic Thor missile and the Able two-stage vehicle which came from the Vanguard launch vehicle. The Thor-Able combination was developed for testing the heat shield for the Atlas missile. I 1958 it was decided to use Thor-Able to launch a moon probe. The first attempt failed, but in October 11, 1958 Thor no. 130 launched the
1 Moon Probe. The launch was only a partial success because the probe failed to reach the moon. Later the Thor- Able was used for launching satellites like the Tiros weather satellite and the explorer VI satellite.
Thor in various combinations with other upper stages became one of the most successful launchers – especially the Delta version has been in use for decades.
Sources on Thor-Able:
Explorer VI Paddle-Wheel Satellite (Video)
The Rocket - The History and Development of Rocket and Missile Technology by David Baker.
Rockets of the world by Peter Alway,