I'm turning 45 this week and would like to know how far I have travelled in space, with the orbit of the Earth around the Sun and with the expansion of our universe.
We put Paul's question to astronomer Carolin Crawford...
Carolin - Well, there are a number of things you can take into account here, Paul. I mean, the first one of course is that the Earth is spinning around the sun, at about 30 km per second. And then the sun is also wheeling around the galaxy at about another 220 km per second. So, if you added all that up together over about 45 years, we reckon youíve travelled at least 350 billion kilometres.
If thatís not enough, just another thing to add into the mix, our galaxy also doesnít stay still. Weíre moving towards the local Andromeda galaxy at something like 400,000 km an hour. So, if you're about to add that in, thatís about over 500 billion kilometres in your lifetime.
Carolin - I bet you didnít realise you're an interstellar traveller.
Paul - Well, there you go.
Kat - Excellent! Thank you very much, Paul.
Paul - Thank you.