A single speck of dust is half way in size between a subatomic particle and the Earth.
15
In zero gravity, a candle's flame is round and blue.
16
Each day, up to 150 species of life become extinct.
-23
The only letter not appearing on the Periodic Table is the letter "J".
180
Sound travels about 4 times faster in water than in air.
408
The bark of an older redwood tree is fireproof.
65