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# Which is More? The Number of Grains of Sand or the number of Stars in the Known Universe? Back to Article
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Which is More? The Number of Grains of Sand or the number of Stars in the Known Universe? # Email This Story

We know the Universe is a colossal place so we know there must be quite a lot of stars. To give you a full perspective a decent perspective our galaxy, the Milky Way, has 150 billion to 250 billion stars.

What do we know also seems to have an infinite number of, the amounts of grains of sand on the Earth is also a very large number. To give you a perspective on that, 1 square meter of sand with a depth of 3 meters contains around 163 billion grains of sand, if you walk along a beach for 30 seconds your likely to have passed 20 trillion grains of sand.

When you think about that it would seem that it is impossible to tell which is more, the number of stars in the known universe or the number of grains of sand on Earth, we can figure it out though.

If we assume each grain of sand has the same size, we calculated how many grains of sand in a teaspoon to a cup, to a gallon and calculate the amount of sand in each beach, desert and plain and then multiply all of that, experts have calculated that there are roughly 7 quintillion  500 quadrillion grains of sand on Earth.

1 quadrillion is 1,000,000,000,000,000, 1 quintillion is 1,000,000,000,000,000,000. So the number of grains of sand is 7,500,000,000,000,000

So how many stars are there in the known universe? Can they even come close to a number like that? Yes they can and let me tell you right now, there are more stars in the known universe than there are grains of sand on Earth.

Let’s assume that each galaxy has an average of 100 billion stars. We know that is less than the number of stars in our galaxy so we are being a bit generous to the sand. Are you ready to here the final answer?

There are 10 billion galaxies that we know of.

That’s 10 billion x 100 billion and that is basically 1 billion x 1 trillion.

That means the number of stars in the known universe are

1,000,000,000,000,000,000,000 stars at least.

That is ten times the amount of grains of sand on the Earth and that is what is considered an extremely close count in the grand scheme of things. 