The heart beats about 100,000 times each day. See more

Leonardo Da Vinci invented the scissors. See more

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

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

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

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

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

Your muscles make up about one-half of your body weight. See more

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

December 1972, astronaut Eugene Cernan (U.S.) became the last person to set foot on the moon. See more

It is impossible for a solar eclipse to last for more than 7 minutes 58 seconds. See more

It takes a plastic container 50,000 years to start decomposing. See more

If you are locked in a completely sealed room, you will die of carbon dioxide poisoning before you will die of oxygen deprivation. See more

More than 50% of the people in the world have never made or received a telephone call. See more

It takes 8 minutes for sunlight to travel from the sun to the earth. See more

A cat's urine glows under a black light. See more