>>939626>>939624And if you take long exposure pics, you need to keep the camera extra still or it will be blurry. If there are moving objects in the pic, you get streaks like pic related. That's also why you see those streaks in the OP pic. They look like satellites moving across the sky throughout the 15sec or whatever exposure.
In a couple years when you are in high school, they might offer a photo class where you can learn all about it!