How far have I travelled?

21 April 2015

Part of the show Could Earth be Knocked Out of Orbit?

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Credit:

Question

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.

Answer

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 you've travelled at least 350 billion kilometres. If that's not enough, just another thing to add into the mix, our galaxy also doesn't stay still. We're moving towards the local Andromeda galaxy at something like 400,000 km an hour. So, if you're about to add that in, that's about over 500 billion kilometres in your lifetime.

Carolin - I bet you didn't realise you're an interstellar traveller.

Paul - Well, there you go.

Kat - Excellent! Thank you very much, Paul.

Paul - Thank you.