who were fighting Mongol invaders, started launching "fire arrows" propelled by gunpowder some 300 metres into enemy lines. 在抗击蒙古军时就开始向300米以外的敌后战线发射“火焰箭”，其靠火药为推动力。

　　When the Song's artillerymen realised that these arrows continued to fly straight 当宋军的炮手意识到，即使火药耗尽、箭上的矢羽烧光，

　　even after their fiery exhaust had burned away their feathers, they removed the fletching and the rocket was born. 这些箭还是继续向前飞进，他们便撤掉了箭上的矢羽，火箭就此诞生了。

　　Almost eight hundred years later Shu Chang, the head of a company called OneSpace, 近八百年后，零壹空间CEO舒畅

　　is trying to build on that historical tradition—though not for military purposes. 正在尝试依据历史传统建造火箭—虽然并非出于军事目的。

　　The charred and twisted remnants of OS-X, the firm's first launch, are strewn across the floor of its laboratory in Daxing, a suburb of Beijing. 公司首次发射OS-X，烧焦扭曲的OS-X残留物洒满了实验室的地板，该实验室位于北京郊区大兴。

　　The launch took place in May, from an undisclosed location in the north-west. 此次试发射发生于五月，其发射地是位于西北方向的一个隐蔽地。

　　OS-X, nine metres tall, climbed to an altitude of 40 km and travelled 287 km downrange. OS-X高九米，可攀上40千米高度，沿试验航向的里程为287千米。

　　It remained airborne for five minutes before crashing into desert sands. 在撞入沙地之前，其在空中保持了5分钟。

　　This lift-off was a first not only for OneSpace but also for China, 此次离地升空不仅是零壹空间的第一次，同样也是中国的第一次，

　　for it was the first in that country of any rocket built by a private space company rather than a government agency. 因为这是中国首枚由民营太空公司而非政府机构研发的火箭。

　　It was also the world's first flight of a rocket intended to pave the way for a commercial, solid-fuelled orbital launcher. 这也是世界首次旨在于为商业、固体燃料轨道发射器做准备的火箭飞行。

　　Solid fuel is easier and cheaper to handle than the liquid variety, which requires tanks and pumps, 相比需要容器和抽运器的液体燃料，固体燃料更轻且更便宜，

　　and its higher density means that rockets which use it can be made smaller than their liquid-fuelled brethren of equivalent lifting capability. 固体燃料的高密度意味着使用固体燃料的火箭体积可以比同运载能力的液体燃料火箭更小。

　　Fine-tuning the flight of a solid-fuelled rocket is harder, though, because the supply of fuel to the motor cannot easily be regulated. 调整固体燃料火箭的飞行更加困难，因为无法轻易控制其发动机的燃料供给。

　　For that reason American space companies have followed the liquid-fuelled path trodden by government space agencies around the world. 因此，美国太空公司依照政府太空机构液体燃料推进的方式行事。

　　The relative disadvantages of solid fuel do, however, diminish as rockets get smaller. 然而，随着火箭体积的缩减，固体燃料的相对劣势确实小了。

　　And since OneSpace is not planning to hoist into orbit the multi-tonne loads carried by, say, the Falcon Heavy lifter of SpaceX, 由于零壹空间不打算将由起落架（比如SpaceX的重型猎鹰起落架）搭载的多公吨负荷吊入轨道中，

　　America's leading private space company, the firm hopes that the simplicity of solid fuel will offset its disadvantages. 美国主要的私人太空公司希望固体燃料的简易性将抵消其缺点。