Stars

📖 In short

A star is a huge ball of very hot, glowing gas that makes its own light and heat. The Sun is a star, the only one close enough for us to see as a big ball. Other stars are very far away, so they look like tiny shining dots in the sky.

🤩 Did you know?

The nearest star after the Sun is more than 4 light-years away.
Some dead stars are tiny, about 20 kilometers across, but as heavy as the Sun.
The oldest stars formed from the first gas clouds in the universe.
On a clear night we can see only a few thousand stars with our eyes.

🔎 Find out more

🌟 Star colors

Not all stars are white! Their color shows how hot they are: blue stars are hottest, then white, then yellow like our Sun, and red stars are the coolest.

🔍 A star's life

A star is born in a cloud of gas and dust, then lives millions or billions of years burning its fuel. At the end of its life it swells into a red giant, then becomes a small star or explodes in a huge blast.

💡 Why do they twinkle?

Stars seem to blink and twinkle because their light passes through the Earth's moving air, which makes it wobble. In space they don't twinkle.

🎯 Countless

Our galaxy alone has hundreds of billions of stars, and the universe has billions of galaxies. There are more stars than grains of sand on all the Earth's beaches!