The Scale of the Universe - starting in Southampton, UK.




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

He wasn't joking. The universe is really rather quite large. Its almost impossible to get a feel for the distances involved. Anyone who says they can truly appreciate such scales are probably lying. The human brain simply cannot comprehend these great gulfs of space - there are no references. The human eye judges distance by parallax - and this method tends to fail over the distances we are talking about.

Look up at the night sky. The moon, the planets and the stars all appear the same distance away. Any astronomer will know that the moon is quite "close" in the general scheme of things, the planets a bit further away, and the stars are somewhat further away.

So, onto this page. Most of my images are listed by catalogue number, or by type, or perhaps by time. On this page I've decided to put a selection together showing their distances.

First. Next doors house! This is part of a window on a house about 200 metres away. 200 metres is a nice distance we can all understand. We can walk it in the space of a few minutes. We could also, dare I venture, throw a stone that far.

Next up, our Moon. 400,000km. In terms of walking to the next house, the Moon is very long way away. Whizzing down the motorway I might be traveling at 100mph (160kmph). Time to the Moon? About 3 months. Walking at 5kmph, I could get to the Moon in about 9 years of solid 24x7 walking years. That doesn't sound so bad. Then compare this with the fact I could walk from London to Paris in 3 such days.. and I could walk to Sydney, Australia in 4 or 5 months. So we get a feel for it. The moon is roughly 25 times further away from London than Sydney is. I can just deal with that in my head.

Mars. 60 million km. Mars was very close when this image was taken in August 2003. 60 million km is about 150 of those Earth - Moon distances. Well over a thousand years walking time. Rather beyond a human life span. Lets get back into our car. Time is then down to 42 years. So if I set out now, I'll get there some time in my 70s. Of course, I'd have to find roughly 4million to pay the petrol bill. Obviously we need to step up our transport method. Lets get in a jet airplane. Travel time by plane - maybe 10 years.

Next up is Jupiter. 657 million km. Well, thats easy. 10 times the Mars distance! 1500 Earth-Moons. 10,000 years walking, 400 years in the car and 100 years in an airplane. Not going to get there in a human lifetime are we? Oh dear, its all starting to get a bit big. As far as light is concerned, it can make the trip in about 35 minutes. From now on, the speed of light is the only thing we can use to measure the increasing distance. (Although chemists will enter into it shortly).

Now a bright star. This image of is Mirach, Beta And. Its about 200 light years away. As the observant among you will have spotted, we have suddenly moved from 35 light minutes to 200 light years. Move out of our Solar System, and the scale changes very quickly. Using our previous modes of transport... walking - 43 billion years (10 times the earth's age), driving - 1 billion years. Airplane... oh give up, such numbers make no sense. All we can say is that it is 3 million times the distance to Jupiter. In a desperate attempt to get a handle on this, compare to our chemist shop in the title quote. Its 3km to my local chemist. If my local chemist was Jupiter then Mirach would be 7 times further away than the Moon. A fair part of the way to Mars.

Moving further out. M16. The Eagle Nebula. This is an open cluster with nebulosity within our own Galaxy. Its about 7000 light years away. This isn't such a bad step up. It might be a 30 billion year drive, but if Mirach is moved to my chemist shop (I have a very understanding chemist you know) then M16 is somewhere in the middle of London, 100km away. Not to be confused with the M16 motorway)Where is Jupiter now? With Mirach at the chemist, Jupiter is now 1 millimetre away...

So, to recap. The Moon is 1/1500th of 1 mm away. Jupiter is 1mm away. Mirach is 3km away. M16 is 100km away. Don't even bother think about how close the Chemist really is now - it won't aid the analogy.

Now we have one chance left before we leave the Galaxy. Globular clusters. This image is M13. Its about 25000 light years away. Yup, we are back to Paris all of a sudden. M13 is 357km away on our current scale.

Sorry folks. Now we have to leave our Galaxy. Our Galaxy is in a group of galaxies with the staggeringly original name of "The Local Group". See here for a decent map of the area. Another member of the group is the galaxy M33, shown left. How far away? Its 3 million light years away. 120 times further than M13. You thought it was going to be much bigger than that didn't you? Where can we put the M33 galaxy in our model? With Mirach still in the chemist shop, M33 is only one 10th of the way to the moon. About 3x the distance to Sydney. There, thats not so bad, is it?

Now we leave the local group for the nearby Virgo galaxy cluster. Pictured is the giant galaxy M85. (ok, so its not a very good picture).This is 60 million light years away! Even this huge distance we can hook onto our model - its twice the distance of the Moon.

Finally we leave Virgo and move to the Pisces-Perseus super-cluster. Here is part of that cluster, Abell 262. Its roughly 260 million light years away. Into our model.. its 5 percent of the way to Mars.

See? Its not that bad. I bet you though we were going to end up extending this analogy to the nearest star! Thats as far as my imaging goes. Put in a nice distant quasar, about 2 billion light years - in our chemist model, its only halfway to Mars.


There, the universe is much smaller than you thought. If a nearby star is in the Chemist Shop, the most distant QSO is not even as far as Mars!
NB Most of the distances and calculations are pretty rough - I have steered away from being exact! Of course, I may have ended up an order of magnitude out here or there, please feel free to correct! In case of major discrepancy, its always reality thats got it wrong.