You think you've seen it all, but really there's so much about the universe we really don't know at all. The world is full of curiosities for us to explore and sometimes things that seem mundane actually have hidden secrets that make the simplest things seem unbelievable. Like the inside of a burning log, for example. Who thought it would be as cool as that?
Here are 21 fascinating pictures you've never seen before:
1. The Northern Lights from space\
2. George Washington's Teeth
3. The inside of a burning log
4. Cancer cells under an electron microscope
5. What pugs looked like before selective breeding
