A cubic yard of air weighs about 2 pounds at sea level.
31
Pumice is the only rock that floats on water.
14
The smell of freshly cut grass is actually a plant distress call.
31
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
Only 12,000 years ago there was a species closely related to modern humans called Homo floresiensis that had been living on an Indonesian Island. They used fire and rather advanced tools, yet were only about 3 feet tall and weighed around 25kg.
15
Each day is longer than the previous on by 0.00000002 seconds which is 13 seconds each century!
116
Most dust particles in your house come from dead skin.
48
In Arizona, a solar wind energy tower has been proposed that would generate as much energy as the Hoover Dam.
5