When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
Every day, plants convert sunlight into energy equivalent to six times the entire power consumption of human civilization.
9
It takes a photon 170,000 years to travel from the core of the Sun to the surface, but only 8 minutes to travel the rest of the way to Earth.
6
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
Cellophane is not made of plastic. It is made from a plant fiber, cellulose, which has been shredded and aged.
44
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
Liquid TIDE laundry detergent glows under a blacklight.
96