Counting the stars

On a clear night, far away from streetlights, go outside and look up. Let your eyes get used to the dark. Slowly, more and more stars appear. Tiny twinkles everywhere.

How many can you count? On a very dark night, you might be able to see a few thousand stars with just your eyes. But that is only a tiny fraction of them. Scientists think there are more stars in the universe than grains of sand on all the beaches on Earth.

What is a star? A star is a giant ball of very hot gas, glowing because of the energy deep inside it. Our sun is a star. It looks much bigger and brighter than the others only because it is so close to us.

The next nearest star is so far away that its light takes more than four years to reach us. That means when you look at a star, you are seeing light that set off a long time ago. Some of the starlight you see tonight left its star before you were born.

Stars come in different colours, if you look carefully. Some look a little bit blue, and those are the hottest. Some look a little bit orange or red, and those are cooler. Our sun is yellowish-white.

Stars are born and stars grow old. They are born inside huge clouds of gas and dust called nebulas. After millions or billions of years, some swell up into giants, and some explode. What is left drifts through space and helps make new stars and planets. The iron in your blood and the calcium in your bones were made inside stars, long ago.

Long ago, people joined the stars up into pictures, called constellations. In winter in Britain, look for Orion, with three bright stars in a row for his belt. And all year round you can find the Plough, seven stars that look like a saucepan.

Travellers used the stars to find their way, across deserts and across oceans. Muslims read in the Qur’an that God made the stars to guide people. By them, travellers find their way in the dark, on land and sea.

Long ago, Muslim astronomers studied the stars and wrote down their names. Many star names we still use come from Arabic. Aldebaran means “the follower”. Vega comes from a word for a swooping eagle.

In the Torah, the first part of the Jewish Bible, God takes Abraham (peace be upon him) outside one night. He tells him to look up and count the stars, if he can. Of course, he could not. And a Psalm says that God counts the number of the stars, and gives every single one a name.

At Christmas, Christians remember the wise men who followed a bright star a very long way. Many families put a star on top of their Christmas tree.

Imagine that. Every star has a name. Even the ones too faint to see.

So next time you are out on a clear night, look up. Choose one star. Give it a quiet hello.

Watch together

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