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
Pumice is the only rock that floats on water.
14
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
A cubic yard of air weighs about 2 pounds at sea level.
31
If the chemical sodium is dropped into water it will immediately and violently explode.
67
The weight of a carat (200 milligrams), standard unit of measurement for gemstones, is based on the weight of the carob seed.
51
The left ear is more responsive to words of love and emotion whispered into it than the right.
40
Sound travels fifteen times faster through steel than through air.
134