Oxygen, carbon, hydrogen and nitrogen make up 90% of the human body.
118
In zero gravity, a candle's flame is round and blue.
16
The force of a suction cup is calculated using F=AP.
15
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
Because heat expands the metal, the Eiffel Tower always leans away from the sun.
79
Columbia University has developed an artificial tree that passively soaks up carbon dioxide from the air using "leaves" that are 1,000 times more efficient than true leaves that use photosynthesis.
15
The brain case [of Neanderthals] on the average was more than 13 percent larger than that of the average of modern man
61
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108