A boeing 747's wingspan is longer than the Wright brothers' first flight (120 feet/36 meters). See more

After billions of years, black holes become white holes and they spit out all the things they sucked up. See more

There are more bacteria in your mouth than the human population of the U.S.A. and Canada combined. See more

It takes about 20 seconds for a red blood cell to circle the whole body. See more

Human thigh bones are stronger than concrete. See more

One quarter of the bones in your body, are in your feet. See more

You're born with 300 bones, but when you get to be an adult, you only have 206. See more

Astronauts grow taller in space. See more

The human heart creates enough pressure when it pumps, to squirt out blood 30 feet high. See more