When you think about a rocket as a whole its hard to imagine how to works. It might even seem mysterious that it’s able to take off and break through Earth’s gravity on its way to space. But a rocket is really just a collection of parts. To understand a rocket, you’d have to...

Imagine a big black box. You do not know what's inside and there's no way to open it. What you do know is that if you touch the box it emits a low vibrational hum. There's no way of telling how it makes that sound. You might speculate there's some kind of speaker inside but there's no way to be...