Solar system models, true to scale
The solar system model that doesn't lie
One scale factor for sizes and distances alike. No exaggeration mode, no inflated planets. Tell it how much room you have — it tells you honestly what fits, and what stays invisible.
The solar system does not end at the last body you can fit. At the same scale, the rest lies here:
The nearest star. At this scale it is farther than any road you could walk — and its disc would still be bigger than every planet in your model.
At this scale light moves at 2 cm/s. A walking person is about 70 times faster — you can outwalk the light. The travel times stay the real ones: the second does not shrink with the model.
Almost all of it is nothing
All four inner planets sit inside the first five per cent of the distance. After that, almost nothing — and that is the property every classroom poster quietly removes.
Print it at true size
A4 · US Letter · CC BY 4.0One sheet per body at true physical size, plus assembly instructions and a closing card with Proxima Centauri. The output is generated as a PDF with explicit millimetre values — still being built, because browser printing is not dimensionally reliable.
Every sheet carries a 100 mm line with millimetre marks. If it measures anything else, the printer scaled the page: set it to 100 % or ‚actual size‘ and print again. Without that check a printout looks exact and is not.
Where the numbers come from
Every value has one source and one reason. The decisions were made once and are written down here — nothing on this page is a rounded memory.
data/horizons-raw.json → every value with its raw lineFor teachers
The model does the teaching, not the text. Four things it makes possible that a poster cannot.
Walk the emptiness
On a 100 m school ground the four inner planets sit within the first five metres. The rest of the walk is empty — and the walking is the lesson, not the diagram.
Outrun the light
In a 1 km model light creeps at 6.6 cm per second; walking is twenty times faster. It still needs 8 min 20 s to reach the Earth. A child who outwalks light understands a light year.
Name what is missing
The page says out loud which bodies are too small to show at your scale, instead of quietly enlarging them. That sentence is the one every poster leaves out.
Use it freely
All print materials are CC BY 4.0: copy them for a class, a corridor or a museum. Attribution is the only condition.