当飞机耗尽跑道时会发生什么？EMAS 可以通过一层在飞机重量作用下碎裂的特殊工程材料来制动冲出跑道的飞机，从而迅速减速。但对于坠落的太空碎片，没有紧急制动装置。
What happens when a plane runs out of runway? EMAS can stop an overrunning aircraft using a bed of specially engineered material that crushes under its weight, rapidly slowing it down. But there's no emergency brake for falling space debris.
我们随同一个研究任务，近距离拍摄卫星在南太平洋上空的火焰重返大气层。而为什么强大的新太空望远镜最终不会重新坠回地球？这完全取决于它们在太空中的运行位置。
We join a research mission attempting to film a satellite's fiery re-entry over the South Pacific from up close. And why don't powerful new space telescopes eventually come crashing back to Earth? It all comes down to where they operate in space.