After a while the style of the blog settles down a little and begins to tell you things you need to know. For instance.
In the Hitch Hikers Guide to the Galaxy, Douglas Adams imagined the Total Perspective Vortex, a device that would give you a picture of the whole infinity of space and within it yourself, an invisible dot on an invisible dot, infinitely small. But just how big is space? Well by one measure it is said that there are more stars in the observable universe than grains of sand on every beach over the whole of the Earth.
This cannot be so.
The Milky Way Galaxy, our home, is an average sized galaxy as it turns out and is estimated to contain 300 billion stars, that’s 300 000 000 000 in longhand. There are some 200 billion galaxies in the universe and being that the Milky Way is sort of average we can multiply those 2 numbers together and wait for it there are about 60 000 000 000 000 000 000 000 stars in the universe (6 with 22 zeros after it). That’s a lot, but just look at all this sand. So much sand, sand between my toes, sand in my shoes, sand, sand and more sand. And this is just one beach.
Now some people with too much time on their hands have calculated that a single sand grain has a mass of 50 micrograms (50 millionths of a gram). By that measure 1Kg of sand (not even enough for a sandcastle bucket) contains 20 000 000 grains and I am looking at a lot of sand on the beach here, buckets and buckets of the stuff.
It’s not enough. Those same people who weighed 1 grain of sand have calculated that all the beaches and all the deserts in all the world contain just 7 500 000 000 000 000 000 grains. Yes, they threw in deserts for good measure! But there are only 17 zeros after that 75 for the number of sand grains. Oh dear, stars outnumber sand by about 8000:1! Space it turns out is very big indeed.
For the moment though this is not important. The sun is shining and fluffy picture book clouds drift by carried in the very slightest of breezes. The breeze momentarily ruffles the flat clam sea, there is barely any swell. There is a pink lobster pot buoy way out to sea, not too far out for this flat sea but too far out given the cold sea, besides today the scenery is close inshore.
It is low tide, maybe a few minutes after, and almost a spring so the water is well down, enough that the fronds of the kelp poke above the water, drooped over on their stalks, tentacles trailing, twisting and clutching at my legs and hands. In summer when the water is clearer and warmer you can swim out here and dive down amongst a forest of brown fronds and later in the autumn the bootlace weed streams out 20 feet in the current.
The kelp glistens, the water surges softly, the cliffs stand black against the bright blue sky and there is not a sound; not a boat, not a gull, not a ‘plane overhead, even the resident oyster catcher pair are missing, nest building has evidently not got under way yet. I drift back to the beach as slowly as I possibly can, then sit on a rock in the sunshine and towel vigorously to bring circulation back to the surface.
Now after that tranquil swim it seems unfair to implode your sense of scale completely, however, just 10 ordinary size drops contain as many molecules of water as there are stars in the universe. I squeeze my swimwear out and spill 1000 parallel universes into the rock pool below.
Water molecules are very small and stars are far away.
I think I need to lie down, far from the sound of the waves on the beach, preferably where I cannot look up at a clear night sky and definitely without this sand between my toes.
[The original figures for this post come from this link but I had done a very rough calculation myself and came up with 5000 times more stars than sand grains. I did not include deserts and had not thought about molecules of water.]