The thumbnail grows the slowest; the middle nail grows the fastest. See more

Astronaut Neil Armstrong first stepped on the moon with his left foot. See more

Zero point energy is a source of energy which is released when atoms stop moving, at -273 Celcius. See more

Leonardo Da Vinci invented the scissors. See more

Astronauts are not allowed to eat beans before they go into space because passing wind in a spacesuit damages them. See more

The telescope on Mount Palomar, California, can see a distance of 7,038,835,200,000,000 million miles. See more

10% of human dry weight comes from bacteria. See more

About 70 percent of your body weight is water. See more

The typical laboratory mouse runs 2.5 miles per night on its treadmill. See more