meaning of delta e
The Delta E, or Thor-Delta E was an American expendable launch system used for twenty-three orbital launches between 1965 and 1971. It was a member of the Delta family of rockets. The first stage was a Thor missile in the DSV-2C configuration, and the second stage was the Delta E, which was derived from the earlier Delta. Three Castor-1 solid rocket boosters were clustered around the first stage.