There is more stuff in the space than we can see, and that the gravity of this stuff is holding everything together.
宇宙中存在着比我们所能看到的更多的物质，而这些物质的重力将所有的东西都聚集在一起。
Further experiments are testing gravity in space.
进一步的实验要测试太空中的引力。
Imagine that you have a pendulum in outer space, that there is no gravity, nothing.
加上在外太空，有一个钟摆，那里没有重力，没有。
Star System Offers Rare Look at Space gravity.
双星系统使我们可以一窥难得一见的空间重力。
I can be somewhere in outer space where there is no gravity.
外太空，并无重力。
Moon's weak gravity let the gasses slipaway into space.
月球的微弱引力允许气体逃到太空里去。
The general theory adds to this the effects on space and time of gravity.
广义相对论在此基础上加入了引力场对时间和空间的影响。
Before we can travel in space men must escape from gravity.
人类必须脱离引力，才能到宇宙空间去旅行。
The gravity force of a space object depends on its mass.
空间物体的重力取决于物体质量。
Time management is like gravity. Too much of it, and we're stuck in place. Not enough of it, and we're lost in space.
时间规划就像重力，过多则固步不前，过少则飘然若失。
Time management is like gravity. Too much of it, and we're stuck in place. Not enough of it, and we're lost in space.
时间规划就像重力，过多则固步不前，过少则飘然若失。
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