Tuesday, 27 September 2011
Stars are the shining globes of gas. Their heat comes from deep inside, where hydroyen is turned into helium, giving out nuclear energ. When the hydrogen present in a star is exhausted, it eventually dies.Galaxies are the assembly of millions of starts.
Sunday, 25 September 2011
Saturday, 24 September 2011
There are more stars in the Universe than there are grains of sands on all the beaches in the world. The Universe is so vast that a ray of light travelling from a remote part of Outer Space takes millions of yeras to reach the Earth. So, when astronomers abserve the most distant galaxies, they see them as they were when they were formed, millions and millions of years ago- only one billion years after the birth of the Universe itself. Radio -telescope are used to study these galaxies, and the further away they are, the further back we look in time.