The bark of an older redwood tree is fireproof.
65
In zero gravity, a candle's flame is round and blue.
16
Optical illusions occur when what the eyes see conflicts with what the brain expects.
75
Hot water can freeze faster than cold water.
181
The most expensive material on the planet is antimatter - worth $62.5 trillion per gram.
18
The sun is 330,330 times larger than the earth.
75