Indoor pollution is 10 times more toxic than outdoor pollution.
62
The average temperature at 40,000 feet above sea level is -60 F.
56
Iron weighs more after it rusts.
68
The Earth's atmosphere weighs about 5.5 quadrillion tons.
108
One cubic foot of gold weighs more than 1,200 pounds!
78
Scientists at the Zhejiang University in China have developed an ultra-light material known as carbon aerogel.
3
In zero gravity, a candle's flame is round and blue.
16
0.3% of solar energy from the Sahara is enough to power the whole of Europe.
310