27 Fascinating And Strange Facts About Water

    There are at least 16 distinct kinds of ice.

    1. There are about 1.5 billion cubic kilometres of water on Earth – that's 1.5 billion trillion litres, or 800 trillion Olympic swimming pools.

    2. If all that water was evenly spread over the Earth's surface it would have a depth of 3,700 metres.

    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 fresh water.

    4. Water is sticky. The molecules love to stick to things, especially each other. It's what gives it such a large 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 sulphide (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 biggest known cloud of water vapour was discovered by Nasa scientists around a black hole 12 billion light years from Earth. There is 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 covered by 10 thousand trillion tons of snow and ice.

    10. There is ice on the poles of the moon, and on the poles of Mars and Mercury.

    11. There are at least 16 different kinds, or "phases", of ice. All of them have different 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 foetus is around 95% water for the first months, getting to 77% water at birth. In a 70kg person, there are 42 litres of water.

    14. Two-thirds of that water is within your cells.

    15. We each drink around 1 cubic metre (1000 litres) 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 litres of water.

    19.You use 8 litres to flush a toilet – about the same as you use to brush your teeth.

    20. It takes 200 litres of water to produce the coffee beans for one cup of coffee

    21. It takes 15,000 litres of water to produce 1 kg of beef.

    22. It takes 100 litres to make 2 slices of bread and 65 litres to make the cheese filling in your sandwich.

    23. It takes 150 litres of water to make one pint (568ml) of beer

    A kilo of cotton – enough for a shirt and a pair of jeans – needs 10,000 litres 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.

    27. 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 a good 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.

    These facts were compiled with the help of Alok Jha, the author of The Water Book, which was published on 21 May.