# A star for every grain of sand.

1. Nov 24, 2008

### nicodopolis

If this is true, could someone please tell me, if a grain of sand represented the size of an average star what would be the average distance between every grain of sand to give a approx size to the universe.

2. Nov 24, 2008

### mgb_phys

Stars aren't spread randomly throughout the universe - they are grouped together into galaxies.
In the centre of the galaxy stars can be very close together, near us they are around 5-10light years apart, galaxies are about 2-5million light years apart.

A star like the sun is around 1.3million km in diameter, a grain of sand is perhaps 1mm, a light year is around 10million million km

3. Nov 24, 2008

### Janus

Staff Emeritus
So, if the Sun is an average sized star, then a model of our galaxy with each sun the size of a grain of sand would be about 769,231 km across. Or the size of the moon's orbit around the Earth. Alpha Centauri, the closest star to our own would be 33 km from our Sun.

4. Nov 24, 2008

### nicodopolis

Thank you, though is it still possible to know the size of the universe and how many stars(grains of sand) fill it and then if they were equally distant from eachother, what that distance would be? *** for a guess, would i be right in saying that the scaled down universe would be size of our galaxy for instance and if every grain of sand were equally distant from eachother, that distance would be 500miles.
Also scaling down the sun to the size of an atom that makes up silver, would we be able to see the scaled down universe in a real sense.