1 Name the star nearest to the Earth. 2 Why does it appear brighter and hotter than other stars ? 3 How much time is required for light to reach the Earth from this star ? 4 Give the composition of this star. 5 What is the source of energy of this star ?

1 Sun is the star nearest to the Earth. 2 The Sun appears brighter and hotter than other stars because it is nearest to the Earth as compared to other stars. 3 The light from the Sun reaches the Earth in 8 minutes and 20 seconds. 4 The Sim consists of 70% hydrogen gas, 28% helium gas and 2% of heavier elements such as carbon, nitrogen, oxygen, etc. , 5 In the Sun nuclear fusion of hydrogen to helium, with the release of large amount of energy takes place.