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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The gleaming white Ares I-X, at its core, is a giant solid rocket booster.

闪闪发亮的白色战神i - X的核心是一个巨型固体燃料火箭推进器。

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The object was too light to be a brick, but it was the same density as a piece of foam from a solid rocket booster.

这一物体太轻了而不可能是一个砖，然而它和固体燃料助推器上的泡沫的密度是相同的。

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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

It reached Mach 4.8 in less than half a minute powered by a solid rocket booster.

NPR: Experimental Air Force Aircraft Goes Hypersonic

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

BBC: Iraq 'could build N-bomb'

The space shuttle uses ATK's four-segment solid rocket boosters (SRBs) to do the major part of lifting the shuttle stack off the Earth.

BBC: New rocket could lift astronauts