How Far Away is Mars?

Many thanks to @Heidi_BT for bringing this one to my attention!

It's no easy task to get your head around the mind-wibbling distances involved in taking an interest in astronomy, and it's even harder to think of ways of helping others to get their heads around it too. The Hitchhikers' Guide to the Galaxy* has a stab at it...

"Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space..."

... but even that doesn't make it sink in. Fortunately there are people like David Paliwoda and Jesse Williams about who are happy to put some real effort into it.

So how far is it to Mars? Make sure you're sitting comfortably, and make sure you have an ice pack to hand for soothing your brain which, if it's anything like mine, will be in danger of melting after you've watched this.

* Brought to our Earthly attention by the late, great Douglas Adams.