In 1846 Vienna, childbed fever caused death among many pregnant patients. Consequently, Dr. Ignaz Semmelweis began an experiment where his doctors washed their hands. Learn more about this experiment on the Science Channel's "100 Greatest Discoveries."
After being pulled out of his home by a tornado, a man lands in a nearby field with no significant injuries. The strength of his bones protected him. Bones' resiliency is discussed in this Discovery Channel video.
How much muscle can a human actually build? Tests on mice show that it's possible to genetically build muscles that don't weaken with time or age. Learn more about muscles on The Science Channel's "Kapow! Superhero Science."
Shortly before leaving to go on a zero-gravity flight, physicist Stephen Hawking spoke with reporter Irene Klotz. Learn how Mr. Hawking, who has ALS (Lou Gehrig's Disease), uses his eyes to speak through a computer in this video.