4M Solar System Model, not to scale

There are a lot of good websites on astronomy, the solar system and orrerys.

In my excitement I forgot to photograph the sprues before they had been assembled and painted, however the back of the box gives a good idea of what is included in the kit. In addition to a set of acrylic colours a sachet of “glow in the dark paint” is provided, the sachet glows when moved out of the light into a dark place.

4M make a wide range of educational toy/kits easily found in hobby shops, science museum shops and online. This one is suitable for ages 8 and over.

The planet sizes are not proportionate to the real things, nor do the “surface details” bear much relation to the real thing, except in the case of Earth where the landmasses are faithfully reproduced. Before detaching the parts from the sprues I made a note of the diameters of the planets. In this way after snapping the planet halves together I was able to check which was supposed to be which. They do snap very tight, so it is a good idea to put the pre-coloured Saturn’s ring in position before snapping the halves together, no need to test fit.

The metal pins or bars provided are generally a tight fit in the planet, but a fairly loose fit in the rotating radius arms, so it is best to loosely try the pins before pushing them hard into the chosen planet. The radius arms are very close together. This means the whole unit is still stable with all planets in alignment on one side, but it also means that the builder needs to carefully choose the appropriate vertical height of pin for each planet so that they do not collide but can be moved past each other. The instructions imply that the pins are longer than they really are and this requires a bit of experimentation to get right.

I also cut out a small cardboard pointer which I pushed onto the Earth’s pin to act as an indicator for the Moon’s position, for my own information.

I painted the planets before assembling them to the radius arms, ignoring the colourful box art and based the colours loosely on wikipedia colour photos of the planets.  

I used almost all the provided tub of white acrylic and added a dash of the provided strong colours to produce a toned down scheme. In many cases I further toned the colours down by applying a topcoat wash of model acrylics.

Sun – bright yellow

Mercury – light brownish – dark brown overpainted with thin wash of “dirty brown” acrylic

Venus – almost white – pale yellow overpainted with white

Earth – blue with green/ brown continents and white polar caps

Mars – red – red-brown overpainted with brown wash

Jupiter – pink with red spot, bands of pale blue overpainted with thin grey wash

Saturn – yellow and pink stripes, overpainted with pale yellow

Uranus – pale blue

Neptune – mid blue with pale blue stripes

(Obviously this is a modern set that conforms with the current thought that Pluto is no longer a real planet but a dwarf planet and so not worthy of including in the set. Ed)

This is a neat little kit. It would be churlish to complain that the surface details are “imaginative” and the provided colours are unrealistically strident.

I have a passing interest in astronomy and this orrery is helpful in visualising the motion of the planets. What I do is get today’s positions of the planets from one of the online orrery sites and move my orrery to line up with that. Repeating this week by week, one quickly gets a feel for the way the inner planets scoot around. The outer planets by contrast swing round much more sedately.

The target audience of 8 year old children would not doubt have great fun painting the planets. Adjusting the pins so that the planets rotate past each other would no doubt be character building for them.

http://en.wikipedia.org/wiki/Solar_System_(planetary)

http://www.nasa.gov/topics/solarsystem/index.html

http://www.schoolsobservatory.org.uk/astro/solsys/orrery/

Jeff Simpson