The ISS is far bigger than either the Salyuts or Skylab. In an uncontrolled deorbit, pieces of debris “up to car and train size,” say experts on the official ISS space station advisory committee, will rain down from the sky. NASA confirms this would pose “a significant risk to the public worldwide.”
对比记忆：画表格对比各算法特点
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The same is done for your target point within its own cluster (finding paths from all its border points to your actual destination).