论文部分内容阅读
想到太空,也许你会认为它与你相隔万里之遥。其实,从你家门口的台阶一直向上,大约30千米的高处便是太空了。你当然可以徒步30千米,只不过会特别累,还很可能引来你的满腹牢骚。但是要想垂直上升30千米,你便需要搭乘火箭了。火箭其实非常不适合飞进太空,因为没有足够强悍的燃料能将整个火箭一下子就推送到太空中。为了将火箭送上太空,人们所能采用的唯一方法是:在火箭升空后将它的一部分抛弃,这让火箭剩下的部分变轻,因而更容易被送进太空。
Think of space, maybe you will think it is thousands of miles away from you. In fact, the stairs from the front of your house have been upward, about 30 km in height is space. Of course, you can walk 30 kilometers, but will be particularly tired, it is still likely to lead your grudge. But if you want to go up 30 kilometers vertically, you need a rocket. In fact, the rocket is very suitable for flying into space, because there is not enough tough fuel can the entire rocket suddenly pushed to space. To get the rocket to space, the only way people can take it is to throw away a portion of the rocket after it’s emptied, leaving the remainder of the rocket lighter and making it easier to get into space.