Wednesday, November 24, 2010

The Scale of the Solar System

What does our solar system consist of? The Sun and eight (or nine) planets? A star and some sphere orbiting it? When you see a picture of the solar system, you often see a nice row of balls of different colors and sizes. You might read that some of them have moons (like we have our Moon). If you read further, you will learn about asteroids and comets, too.

One wonderful thing about the bodies orbiting around Sun (as everything, in the end, goes around it) is that they come in all sizes, all affected by gravity of each other.

Inspired by a link Aleksi Eeben shared on Facebook, I wanted to explore the scales of objects in our solar system a bit. I spent some four hours playing with Gimp, looking for information and NASA photos from Wikipedia and creating something that - I hope - someone will find interesting. (Note that the lengths mentioned are the longest axis of the object, unless stated otherwise.)

Unfortunately, I ran out of planets. After Saturn and Jupiter there were no planets left - in the final picture you'll find our good ol' yellow Sun shining. I know that there is another comparison (gif animation) circulating over the Net, so I am not continuing further.

If you like this image series, hate it, or have some ideas (I cannot promise I will fix possible errors...), just leave a comment!

Let us start with some buildings on Earth (with one airship), in the company of some dangerous Near Earth Asteroids, with one corner of Toutatis showing in the background...

Now we zoomed out ten fold, revealing the shape of Toutatis. Next to it we have some other rocks - namely the periodic comet Tempel 1 and Dactyl, the tiny moon of asteroid Ida. In the background there is already Mars' moon Deimos looming.

Now we have a nice collection of greyish interplanetary objects in view. In company of the irregular Deimos we can see the famous Ida (whose moon we already saw), Halley's Comet (only the nucleus - the tail can be millions of kilometers long) and the asteroid Eris, whose shape is very peculiar. In the background we see the first actually spherical object in this series.

The spherical object was Mimas, a moon of Saturn, famous for its crater which makes the moon look like the Death Star from Star Wars! Enceladus' smooth surface is impressive, but these icy moons are quite tiny when compared to Triton.

We have now passed the 1,000 km mark. Triton, which orbits Neptune, is a fascinating little world and a surface with many features. The same cannot be said of Titan, which has an atmosphere that blocks the view to the surface. The boringly gray ball on the right is own Moon. It is only natural to have Earth in the background. But what if it was Titan orbiting us, instead of the Moon?

Earth is much bigger than any moon in the solar system but it is no match to the big boys: the gas planets in the outer solar system. Of them, here we see the cyan-colored Uranus. Its featureless cloud layers may seem pale in comparison with the giant Saturn behind it.

The two giants, Jupiter and Saturn, are here. They fit well in the same picture, but they are overshadowed (or overlit?) by the only star in our solar system.

Maybe I could have spent those four hours better. On the other hand, I think not.


  1. Scale is a wonderful thing to boggle the mind with. Just the other day I was admiring this one:
    I think Barks once drew a highly fanciful Donald Duck story which illustrated interstellar scale by imagining various familiar things like insects magnified by the size difference between our Sun and various stars. It made quite an impression on a young me, I'll tell you.

  2. Very nice. Though it *really* gets interesting when you start comparing stars, galaxies, local groups, superclusters and such :-)

    For instance the distances between galaxies are relatively small, while distances between stars - again relatively - are mind boggling.

  3. This was quite neat and would be fascinating to see in some kind of animated form...

  4. So now I am supposed to feel really small and my problems even smaller? They are still there for me, thank you very much :) Nice work though, nothing wrong with that, it's a pity that whatever we've made here on Earth doesn't really scale well with planets. Of course you could get the opposite effect by scaling down, all the way to microbes, cells, atoms and so on...

    ps. You use "sphere" in singular in the first paragraph (2nd row), shouldn't that be made plural?

  5. Cool pics, what else can I say :)

    Haven't thought about asteroid sizes before, thanks for visuals!


  6. Mikko, this is so cool! Very helpful for comparing the sizes