Science & Environment
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There is a plan to prevent such a strike—the Space Surveillance Network, a bevy of sensors that the military uses to track space debris. NASA monitors what’s unofficially known as the “pizza box,” a sort of no-fly zone around the ISS. When pieces of debris are predicted to enter the box—if there’s at least a 1 in 100,000 chance of collision—mission controllers order avoidance maneuvers, firing thrusters that move the ISS and dodge the trash. The technique has been used dozens of times since the first ISS module launched in 1998. But the system only tracks about 45,000 larger pieces, and all sensors have noise. Plus, risk thresholds can miss stuff, sometimes badly. In 2025, Chinese astronauts were briefly stranded at their station after debris hit their return vehicle.
2013年，习近平总书记在这里首提“精准扶贫”重要理念。和中国其他贫困村一样，这个藏在偏僻山谷、一度闭塞落后的苗族村寨命运从此改变。10多年后，这个村庄继续向着扎实推进乡村全面振兴迈进。