The solar system on a child's wooden desk by a window, a pencil cup and a notebook beside it, its nine coloured arms fanned out round the purple Sun

Solar System

Swing every planet round its own ring. They never fall out of order.

How the sky turns

A solar system for one desk.

The Sun, eight planets and Pluto, each on its own arm, all turning round one post. Keep scrolling to fly in.

Nine rings to follow.

9 grooves run round the plate, from 1.9 in across for Mercury to 7.6 in for Pluto, crossed by 9 spokes 40° apart. Every planet sits right over its own ring.

Ten pieces on one post.

Spread out here so you can see the stack: each arm is a ring round the centre post, one step higher than the arm below, with the Sun on top.

Pluto's arm rides over everything.

The top arm has nothing above it, so it swings nearly all the way round its ring, passing over every other planet.

Sweep it back and it herds the rest.

Each planet sits at the height of the arm above it, so none can slip past another. Pluto gathers Neptune, then Uranus, and so on down to Mercury, always in order.

Set the sky your way.

Fan them out again, outermost first, and each planet lands back over its own ring. Any arrangement works, and Mercury always stays first.

Ten domes, sized in order.

Jupiter is the biggest planet in the set and Mercury and Pluto the smallest, as in the sky. Every one is its own colour, on an arm of another. Drawn here at true size relative to each other; pick one to read it.

Sun

A purple dome 0.98 in across on an orange collar, capping the post above every arm.

Up close

9.1 × 9.1 × 3.3 in and 6.9 oz: about the footprint of a dinner plate, light enough to carry from the desk to the shelf with one hand.

The set from the far side: Pluto's cream arm reaching out over the plate, the purple Sun on its orange collar at the top of the post
Pluto's cream arm is the longest, and the top one: it clears every planet below it.
A low view of the centre post: a rainbow stack of arm rings, each a step higher than the last, with domes on short arms near the bottom
Seen low, the arms climb the post like a rainbow, one ring per planet.
Close on Jupiter's green dome in its yellow-green collar and Saturn's orange-red dome beside it, the grooved plate beneath
Each dome sits snug in a collar at the tip of its arm, right over its groove.
The solar system on a white desk beside a laptop keyboard in soft morning light
Beside the laptop it takes the corner of the desk, not the desk.
A child's fingertips swinging Jupiter's arm round the post
Two fingertips on an arm and the planet goes round its ring.

Set any sky. Never out of order.

The arms climb the post one step at a time, and each planet's dome stands as tall as the arm above it. So a planet can swing up to its neighbour's arm but never under it: whatever you do, the order runs Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto.

Try it on the plate here. Drag the slider to swing Pluto's arm: one way it rides over the others, the other way it pushes them round in a line.

All nine planets swept round to one side of the plate, packed in order
Swept to one side, they pack up tight in the order they orbit.

Solar System

20 pieces, one sky to set.

1
grooved base plate with its centre post
9
orbit arms, one for each ring
10
domes: the Sun, eight planets and Pluto
Size
9.1 × 9.1 × 3.3 in
Weight
6.9 oz
Orbits
9 grooved rings, 1.9 to 7.6 in across
Bodies
Sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
Movement
Every arm swings by hand round the post
Power
None
Material
PETG
The whole set fanned out, every planet over its own ring

Good to know

Does it need batteries or a motor?

No. Nothing in it is powered. Every arm turns by hand round the centre post.

Can the planets pass each other?

No, and that is on purpose. Each dome stands at the height of the arm above it, so the order always runs from Mercury to Pluto. Pluto's arm, the top one, swings nearly all the way round over the others.

How big is it?

9.1 × 9.1 × 3.3 in and 6.9 oz. The plate is 9.1 in across and the Sun sits 3.3 in up, so it suits a desk, a shelf or a classroom windowsill.

What is it made of?

PETG plastic. The plate is tan, and each arm and dome comes in its own colour, so the ten bodies are easy to tell apart.

Which planet goes where?

Each planet sits on the arm whose tip reaches its own groove: Mercury on the lowest, shortest arm, Pluto on the top, longest one, and the Sun on the very top of the post.