1. There are about 1.5 billion cubic kilometers of water on Earth – that's 1.5 billion trillion liters, or 800 trillion Olympic swimming pools.
2. If all that water were evenly spread over the Earth's surface, it would have a depth of 3,700 meters.
3. 97% of the Earth's water is salty. 2.1% is locked up in polar ice caps, and less than 1% is available as freshwater.
4. Water is sticky. The molecules love to stick to things, especially each other. It's what gives it such an enormous surface tension. It keeps you alive: it means water can pull blood up narrow vessels in the body, often against the force of gravity.
5. Water should be a gas at room temperature – all similar molecules, such as hydrogen sulfide (H2S) and ammonia (NH3), are gases. The stickiness of water molecules holds them together as a liquid.
6. Water is the second most common molecule in the universe. The most common is hydrogen gas, H2.
7. the enormous known cloud of water vapor was discovered by Nasa scientists around a black hole 12 billion light-years from Earth. There are 140 trillion times as much water in it as all the water in the world's oceans.
8. All the water on Earth arrived in comets and asteroids. It happened between 4.5bn and 3.8bn years ago; a period called the Late Heavy Bombardment.
9. The Antarctic has been covered in ice for more than 30m years. Right now, it is surrounded by 10 thousand trillion tons of snow and ice.
10. There is ice on the moon's poles and the bars of Mars and Mercury.
11. There are at least 16 different kinds, or "phases" of ice. All of them have other crystal structures.
12. The Sun and other stars like it create the equivalent of 100 million times the water in the Amazon River every second.
13. Your body is between 60% and 70% water. This changes at different times of your life: a human fetus is around 95% water for the first months, getting to 77% water at birth. In a 70kg person, there are 42 liters of water.
14. Two-thirds of that water is within your cells.
15. We each drink around one cubic meter (1000 liters) of water a year.
16. Water expands when it freezes, unlike almost every other liquid. This has been crucial to life – lakes and rivers freeze from the top down, so even though the Earth has faced successive ice ages, there has always been liquid water for life to continue evolving.
17. Hot water freezes faster than cold water. This is known as the Mpemba Effect, and no one knows why it happens.
18. A five-minute shower uses 200 liters of water.
19. You use 8 liters to flush a toilet – about the same as brushing your teeth.
20. It takes 200 liters of water to produce the coffee beans for one cup of coffee
21. It takes 15,000 liters of water to produce 1 kg of beef.
22. It takes 100 liters to make two slices of bread and 65 liters to make the cheese filling in your sandwich.
23. It takes 150 liters of water to make one pint (568ml) of beer
24. A kilo of cotton – enough for a shirt and a pair of jeans – needs 10,000 liters of water to produce.
25. Everywhere there is liquid water on Earth, there is life. Even if that water is nearly boiling, or the area is skin-burningly acidic.
26. There is a hot ocean under the ice crust of Saturn’s moon Enceladus, probably sitting on a bed of rock. Since a hydrothermal vent at the bottom of one of the Earth’s oceans is thought to be the best candidate for where life started on our planet, astrobiologists think Enceladus is an excellent place to look for alien life.
27. Leonardo Da Vinci and Niccolo Macchiavelli once came up with a plan to use water to win a war by diverting the river Arno. Da Vinci was obsessed with water; he drew its vortices endlessly. He also worked out a lot of the science of how it flows, well before the field of fluid dynamics was established.
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