Transit-O 4
Thor DM-21 Ablestar
United States Air Force
Mission
Transit-O 4
Type: Navigation
The Transit-O series of satellites that closely followed the design of Transit 5C-1 were also called “Oscars” (Oscar is the phonetic alphabet for “O”, i. e., operational). They were also called NNS (Navy Navigation Satellite) or shortened NavSat.
Trajectory
The trajectory is unavailable. Check back for updates.
Location
Space Launch Complex 2E
Vandenberg SFB, CA, USA
713 rockets have launched from Vandenberg SFB, CA, USA.

Rocket
Thor DM-21 Ablestar – United States Air Force
- Family: Thor-Ablestar
- Length: 29 m
- Diameter: 1.44 m
- Launch Mass: 51 T
- Low Earth Orbit Capacity: 150 kg
The Thor DM-21 Ablestar was manufactured by United States Air Force with the first launch on 1960-04-13. Thor DM-21 Ablestar has 13 successful launches and 6 failed launches with a total of 19 launches. The Thor-Ablestar, or Thor Able-Star, also known as Thor-Epsilon was an early American expendable launch system consisting of a PGM-17 Thor missile, with an Ablestar upper stage. It was a member of the Thor family of rockets, and was derived from the Thor-Able.
Agency
United States Air Force – USAF
- Type: Government
- Abbreviation: USAF
- Country: USA