Antares 2

Antares 2 (X-259) was an American solid rocket engine stage and engine built by Hercules/ABL / Thiokol.

[1][2][3] It was used from the mid-1960s to 1995, in the Scout and Strypi family of rockets,[4][5] and on the Project FIRE Velocity Packages.

[6] It burned solid propellant – the stage was also the engine's fuel chamber - and was used about 96 times.

[1] Basic details of the X-259 engine:[1] There were various variants:[1][4]