Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
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
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
German chemists made a replica of a trophy the size of one molecule.
68
When you walk down a steep hill, the pressure on your knees is equal to three times your body weight.
199
A coal power station puts 100 times more radiation into the air than a nuclear power plant producing the same amount of energy.
7
One barrel of petroleum holds 42 gallons.
20