What does our Solar System look like and how do our planets orbit around the Sun? How far away is pluto from us? Really is Jupiter that big and we are that tiny?  How many moons are there around Saturn? Who discovered  pluto? Why is pluto not a planet and then a planet again?

All questions which curious 2nd graders ask.  For the second time in a row, we are helping the students to understand our planets, the solar system, traveling to outer space by learning about each of the planets and building a scale model planetarium.

Below you find the resource we have created and are using to build this student build planetarium, including links to some of the videos to explain concepts.

 One of the oldest planetariums

In the living room of a lovely Friesian canalside house is the world’s oldest functioning planetarium. This accurately moving model of the solar system was built between 1774 and 1781 by Eise Eisinga, a wool carder.  This planetarium is build in his living room using the ceiling and every wall, and the upstairs attic for all the clocks and time pieces.

Why did he build it? It was build because a conjunction (when two planets orbits cross) of planets occurred on 8 May 1774. Before it happened, people insisted that these planets would collide with one another, the result being that the earth would be pulled from its orbit and incinerated in the sun. Eise Eisinga wanted to show that there was no reason for panic.


All the planets in Eisinga’s model orbit the sun at the same speed as do the real planets: Mercury in 88 days, the earth in one year, and Saturn in more than 29 years! Even today, after so many years, the actual position of the planets can be seen by looking at this model. Besides this model, Eise Eisinga also built all kinds of special clocks that indicate the day, the date, the rising and setting of the sun and moon, the apparent movement of the heavens due to the rotation of the earth, and other phenomena.

Our Student Build Planetarium

Our student planetarium will not be orbiting around the sun, but it does show accurately the relative distance and the scale of the planets within.  So for example if the sun is at one end of the hallway and is the size of an 8″ ball then Pluto would be at the other end of the hallway 242 paces away and smaller then the size of a pinhead….

Recalculating this for our school building, our model will be is as follows:

Planet Diameter in Inches Distance to next object in ft Object used
Sun 400″ 200Ft(end of hallway Painted Yellow paper
Mercury 1.4″ 0.73ft from Sun golfball
Venus 3.5″ 1.35ft from Mercury tennisball
Earth 3.7″ 1.86ft from Venus tennisball
Mars 1.9″ 2.85ft from Earth golfball
Jupiter 41″ 9.7ft from Mars 4square or beach ball (*)
Saturn 33″ 17.8ft from Jupiter 4square or beach ball (*)
Uranus 13″ 35.8ft from Saturn 4square or beach ball (*)
Neptune 13″ 56.13ft from Jupiter 4square or beach ball (*)
Pluto 0.6″ 73.6ft from Neptune small marble

(*) – we can not make those to true scale so we are using a large beach ball or 4-square ball to show it’s size.