The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
The smell of freshly cut grass is actually a plant distress call.
31
Stephen Hawking once tried to find potential time travellers by throwing a party and only sending out invitations after the party.
17
MIT has developed a camera that captures the speed of light at a trillion frames per second.
20
The sun is 330,330 times larger than the earth.
75
Airports that are at higher altitudes require a longer airstrip due to lower air density.
39
The only letter not appearing on the Periodic Table is the letter "J".
180