Supposedly, it was developed by NASA as a solid rocket fuel.

据说，这种东西最早是由NASA作为固体火箭燃料而研发的。

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Officials say the solid-fuel rocket could reach Israel, southeastern Europe and American bases in the Middle East.

VOA: special.2009.05.23

He adds that the newer version has a shorter launch time, better deterrent capability, and that it is a two-stage rocket using solid fuel that is highly maneuverable.

VOA: standard.2009.12.18

Iraq is also believed to be capable of manufacturing solid rocket fuel.

BBC: Iraq 'could build N-bomb'

As a solid-fuel rocket, this could be fired at short notice from mobile launchers.

ECONOMIST: Nuclear proliferation

As a result, real concerns are beginning to be expressed about the viability of the U.S. industrial base for solid-fuel rocket motors.

CENTERFORSECURITYPOLICY: Farewell to space