【英语时差8,16】用一根绳子连接地球和同步卫星（下）（在线收听）

When you haul something up by rope, you generally think of the object being lifted as the weight. Something we don’t consider is that the rope has to be able to lift itself too. Lift itself!?! What does that mean? Think of it this way. If a ten-foot rope is hanging straight down, the top one inch is supporting the weight of almost ten feet of rope. That’s no problem, but what about a hundred feet? Still no problem? How about a hundred miles? In fact, no rope could support 22,000 miles of its own weight. Not even a cable of the mightiest steel would work. In fact, there is no material you could use that wouldn’t snap under its own weight long before it reached from earth to satellite. And that’s without even adding the weight of the cooler!