1. Over millions of years, hot Orion clouds of gas called nebulae grow until they explode and form huge, blazing balls of fire. This is how stars are born. Our own sun is a star. Eventually, like all stars, it will run out of fuel and die. Don't worry though - this yan't happen tor another 4 bilion years! Stars are sources of light. This is the reason they shine so brightly in the sky. The moon, planets and comets also shine. but they don't give out their own light. They lust reflect li from the sun. Stars are very, very far away. In fact, when their light reaches our eyes, we sometimes see them as they were thousands of years agol Our sun is the nearest star to Earth, but it is sbill about 150 million km away! It is part of the Milky Way galaxy a white band of stars that stretches across the night sky There are more than 100 billion stars in the Milky Way and many of them, like our sun, have planets that orbit around them, Constellations are groups of stars. It you draw lines between hem (and use lots of imaginationi) they sometimes look like objects, animals or people. The ancient Greeks thought that Orion looked like a giant hunter with a sword altached to his bell! As the earth moves around the sun, we see the constellations in different positions in the sky at difterent times al the year In the same way, the whole sky seems to move towards the west as the earth rotates on its axis throughout the night. How much do you know about stars? Try to answer the questions. Listen and check. A What are constellations? B Why do stars shine so brightly? • Why do constellations appear to change position? D Which star is closest to the Earth? E What are stars made up of?