制动火箭是运载火箭和宇航器上的一种小型辅助火箭发动机。
发射后差不多三天时间，制动火箭启动了，阿波罗8号飞船进入了月球轨道。
Nearly three days after launch, the braking engines fired and the Apollo 8 capsule went into orbit around the moon.
最后，在围绕地球的轨道运行的时候，计算机会精确地计算出应该在什么时候发射制动火箭以重返大气层。
Finally, when in orbit round the earth, the calculators calculate exactly when to fire the retro-rocket to effect re-entry.
27岁宇航员首次任务只持续了108分钟，但是过程充满了戏剧性：数据传输中断、天线故障、制动火箭与部件分离。
The 27-year-old cosmonaut's mission lasted just 108 minutes and was fraught with drama: a break in data transmission, glitches involving antennas, a retrorocket and the separation of modules.
应用推荐