Synthetic aperture radar

Synthetic aperture radar (or SAR) is a way to use a radar to create a very detailed picture of something far away. Instead of using a big radar dish, you can use a smaller device to send out radar waves. The waves travel to the object and then bounce back. The device you are using can then measure the time it takes the waves to bounce back and build a picture of the object using that information. It's sort of like bouncing a ball off a wall and measuring how long it takes to come back - but with waves of energy instead of a physical ball!