Grains of Sand and Stars in the Universe

I just got in from a walk at night and there are a lot of stars outside. It made me think about stars and grains of sand. Are there more grains of sand on Earth than stars in the universe?

Obviously, we can’t count either but we can estimate. A group of researchers at the University of Hawaii attempted to calculate the number of grains of sand on Earth. After careful estimates of the sand on all the beaches and deserts in the world, they came up with a number of  7.5 quintillion grains of sand (7.5 x 10¹⁸ ). That’s a large number.

It’s just as hard to guess the number of stars in the universe. Estimates are that there are 100 billion to 400 billion stars in a galaxy, and that there are at least 100 billion galaxies in the universe. Let’s just take the small number of 100 billion each. That would make 10²² stars. I don’t even know what the English word for that is.

When I divide the two numbers, number of stars divided by number of grains of sand, I get 1,300 stars per grain of sand.

Astonishing.

When we go out on a completely clear night with no moon, in the desert, and we look up at the sky full of brilliant stars, that number of stars is about 6,000 or roughly four grains of sand’s worth.