If the universe is approximately 14 and a 1/2 billion yrs old, how old is our blue marble? Also why is it considered looking into the past when looking out in space? Wouldn't that make earth the focal point of the universe?
replied to: TimmyP
Replied to: If the universe is approximately 14 and a 1/2 billion yrs...
Earth is around 4.5 billion years old.
When we look at the stars we are see an image of how the star looked when the light left the star.
The farther away the star is, the longer it took light form that star to travel all the way to earth. The closest star is about 4 light years away, so we see the star as it was 4 year's ago.
We are not the focal point of the universe, there probably isn't a center. The current theory of the start of the universe is that it didn't explode outward at a single point, but instead there was a uniform expansion.