Question: How long (approxamte) will it take to reach the end of the universe?

Mark Hill answered on 13 Mar 2011:

Hello Ethboy, I certainly think that you will be late for tea!

This is definitely not my area of expertise, by any stretch, but I am really interested in it. Perhaps Professor Brian Cox, (book – ‘Why does E = mc(squared)’) or Stephen Hawking (book, – ‘A Brief History of Time’) could answer it properly.

However, this is what I understand (this will be interesting – a policeman giving an answer on astrophysics!).

It is generally believed that the universe is still expanding, away from the ‘Big Bang’, thought to be some 14 billion years ago. Astrophysicists can measure how far away galaxies are by such things as their colour, radiation output and relationship to other galaxies.

Now, let us assume that they are right, although, if the universe is still expanding, what is it expanding into and what is beyond it waiting for the universe to reach it? Perhaps that problem is for another time.

Our problem is being able to travel fast enough, in our very short lives (in astronomical terms), to be able to reach the edge of the universe. I don’t think that travel at the speed of light (roughly 670 million mph) would do us much good. After all, some of us struggle to drive at 30 mph without crashing!

It is thought that the furthest galaxy is about 10 000 (10 billion) light years away. So, if a light year is the distance covered by something in a whole year, travelling at the speed of light (670 000 000mph), then it would take you at least 10 000 000 000 (10 x 10 to the power of 9) years.

This is a really good question, on a subject that I know very little about, but that I find fascinating.

Thank you very much.

Mark.