If you think about it, your body is a strange, mysterious machine. One day, you woke up with it. Then, you get to spend years living inside it and using it. Have you ever taken the time to really think about it and the different things that it does? Or how it makes you feel? Next, think about this place you live. Earth is a huge planet with countless undiscovered places. But, that huge planet is spinning in an endless void known as the Universe that we may never discover the secrets of. The more you think about things in life, the weirder everything will seem. These 17 things listed below are no exception. Once you think these things, you can’t un-think them.