What Are The Threats To Earth From Space?
By Philip Browne
Published: November 13, 2013.
We know that the Big Bang of 13 billion years ago saw the birth of the sun and many other planets. It just took an instant for the birth of the universe and the universe has been growing or expanding at the speed of light ever since. There are 100 billion galaxies within the universe and our galaxy is just one of them with over 100 billion stars.