Big Numbers


Amaze your friends with some mind boggling facts


Earth's atmosphere          1 litre juice carton
There are roughly 10^22 litres of air in the atmosphere.  Remember, that 1022 litres is 10000000000000000000000 cartons like the one above. By a mind boggling coincidence this is the number of molecules in a litre of air and about the number of stars in the universe.
Milky Way from Wikipedia and Hubble Of course this is approximate, there are a lot more air molecules squashed into a small space near the surface of the Earth than at the top of Mount Everest because of the pressure difference. And of course we can only estimate the number of stars in the universe because counting them at the rate of 1 a second would take 3*10^14 years which is a lot longer than the universe has been in existence! alaxies from the hubblt telescope courtesy Wikipedia


Things that look like dots in the photograph on the right are galaxies, each containing billions of stars. It's fair to say that the world in which we live is in scale half way between the world of atoms and the world of galaxies and the universe as a whole.

Our own Galaxy, the Milky Way has between 200 and 400 billion stars. If you are having difficulty imagining these numbers don't worry, they are not easy for anyone. This is why we put numbers on them like 4 x 10^11. (4 x 1011) It's just a short way of writing 400 billion because no-one can really imagine 400 billion. In Computing terms writing 400 billion is an abstraction of the real thing.