The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
Scientists are now able to grow 'beating' heart tissue in a lab!
162
Dr.Jonas Salk, the man who came up with the cure for polio, didn’t patent the drug. This made the drug more affordable to the general public, and he lost out an an estimated $7 billion dollars for himself.
41
One barrel of petroleum holds 42 gallons.
20
The average home creates more pollution than does the average car.
33
Nylon is made from coal and petroleum.
42