Does there exist any reasonably observable scale model of the Solar System?

Factual Questions
1

I was reading Bill Bryson’s A short history of nearly everything and while trying to put the scale and distances of our solar system into perspective, he explained that to even put on paper a scale model of the solar system, if Jupiter were the size of the period at the end of this sentence, neptune would be both 35 feet away and microscopic. Wow! Talk about putting something into perspective…

So anyway, I started wondering - does there exist any reasonable scale model of the solar system on earth? I’m imagining maybe a gymnasium-sized model in some science museum or something like that.

Is it even possible to make such a thing while preserving the size relationships between the Sun and the planets?

2

When I was a kid, we used to go to the National Geographic building in Washington, DC.
They had a scale model of the Solar System, with little lights cycling to show how fast the planets moved. They didn’t have the actual planet dimensions modeled, though. As I recall, the model was maybe 15’ long.

3

According to the National Optical Astronomy Observatory, if the Earth were the size of a peppercorn you would need over a thousand yards to show all the orbits. I assume this means that the entire model would be at least two thousand yards wide.

4

They have something along the sidewalk on the Mall side of the Air & Space Museum in DC, running towards the Castle (the old Smithsonian). I think that the sun is about grapefruit sized, and most of the planets are like BBs. So while the actual planet size might be a bit off so you can see them, the distances are relative, and it’s an interesting perspective.

5

There are several “large scale” models - where the sun is a water tower or something. I’m guessing there are “building scale” ones also, but don’t know of any for sure.

Brian

6

There are some on-line attempts

http://en.devhed.com/solar-system/ (with an explanation of the difficulty of actually sqeezing anything meaningful into a 1280 pixel screen)
http://www.troybrophy.com/projects/solarsystem/index.html
And here is a walk-around attempt, althugh I do not know how accurate the orbital scale is.

http://www.arm.ac.uk/astropark/solar_system.htm

And an elementary school set of instructions to build a model
http://epswww.unm.edu/iom/epo/scale/outdoorscale.pdf

7

Why not try a logarithmic scale model? You might need separate scales for the sizes of the celestial bodies and the distances between them, though.

8

The SpacedOut Project has created one spanning the entire British Isles. Amongst the major objects, the Sun is at Jodrell Bank in the Midlands, Neptune is in Northern Ireland and Pluto at Aberdeen in the north of Scotland. There are more minor objects in both Shetland and Cornwall, at opposite ends of the country.

9

ETA: Never mind, screwed something up with the conversion factors. Next try’s a charm.

10

What about the set of pictures that goes from Earth to Antares? Or this video?

11

It’s not only possible, it’s been done many times.

I’ve been to the one in Ithaca, NY.

I remember participating in the sports-field one (or something very similar) in my high school astronomy class.

I created a scale Earth-Moon model for my students when I was a TA at UC Santa Cruz:

Say San Francisco (which is about 8 miles wide) is the Earth. On that same scale, roughly where should the moon be?
a. San Jose
b. Santa Cruz
c. San Luis Obispo
d. Los Angeles

The correct answer is c, San Luis Obispo

12

The big problem you’re going to run into trying to build this is that the planets are absolutely dwarfed by the distances between them, especially as you get to the outer planets. I put together a table showing how far each planet would be from the sun* and how far away it would be if you tried to build a model with the earth 10 feet away. Here’s how it looks (all numbers are feet):



Planet		Distance	Radius
Mercury		4.59		0.00
Venus		7.16		0.00
Earth		10.00		0.00
Mars		16.39		0.00
Jupiter		53.69		0.00
Saturn		98.88		0.00
Uranus		197.66		0.00
Neptune		298.29		0.00

You can immediately see a small problem with trying to build this. For the record, the actual radius for Jupiter is .0047 feet, which is a little over 1/20th of an inch. Earth’s radius is a little over 1/200th of an inch; I’m not sure if I can even see that.

*I used the aphelion distance for every planet. I’m not sure if that’s the best number, but since we’re talking order-of-magnitude here, I figured consistency was the most important thing.

13

I’m drawing a blank on where, but I’ve seen a scale layout of the sun and nine planets (before they changed their minds about Pluto!) that was miles long. Most of it was within the building, but Pluto was a small painted spot on the sidewalk a few miles away from the building.

Some poking around… Here’s one in Peoria, IL

It’s 47 miles from the sun to Pluto Assuming they kept the same scale all the way through, Pluto is about as big as the keyhole on the museum’s door.

14

That must be one gigantic building if it’s to scale! The Carl Sagan Planet Walk, mentioned by Anne Neville above, is only about a mile from the sun to Pluto. The inner planets are on the same block as the sun. You’ll have to cross the street and go around the corner to get to Jupiter. Saturn is another block and a half away from Jupiter. Uranus is another 2.5 blocks away from Saturn, and Neptune is 4 blocks from Saturn.

15

If we take the order-of-magnitude assumption that an object a millimeter in diameter is about the smallest thing the average human can see with an unaided eye at a negligible distance, Jupiter is the only planet you’ll be able to see without a magnifying glass or a microscope. (1/20th of an inch is exactly 1.27 mm.)

16

Here you go. Not what the OP was after, but a terrific model nonetheless.

17

That would work, of course, but it feels like cheating.

18

As other have said, the range of sizes precludes a scale model that includes the planets and their satellites to the same scale as the distances between planets.

Using the model that was 1.3 km long, to the same scale as that length being the distance from the sun to Pluto the sun would have a diameter of about 3/32".

19

Here’s one in Maine that is apparently completely to scale. It’s 40 miles long and they say the Earth is the size of a softball. Jupiter is 5 feet.

20

The article doesn’t say whether they included the sun. If my calculations are correct, the sun at that scale would be almost 50 feet in diameter.