Large sized, scale model of the solar system.

[Uncwilly]

I am working on plans for a very large, scale model of the solar system. This is based upon the size (and location) of an existing object, thus the scale is not subject to change. The scale is such that the 8 major planets will be scattered across a major metropolitan area. My plans are to present this to the organization that I hope will spearhead the project.

I have been using data from online sources (mainly wikipedia), a spreadsheet to do the scaling calculations, and google earth to map out perihelion, aphelion, and suggested locations for the models. I would like this to be the most detailed of the large scale models.
Thus in addition to the sun (the scale setting object) and the 8 major planets, I am looking to site a number of other objects.

• Confirmed dawrf planets
• Probable dwarf planets.
• All other gravitationally rounded objects (moons).
• At least the 3 largest moons per planet (for those that have them).
• A few comets (am working on the list of those visited by spacecraft, starting with Halley and 61P.) May look to add the largest.
• Some or all of the other minor objects visited by spacecraft. Various asteroids (Vesta for sure). MU69 for sure. Some objects have yet to be visited, but should by the 'big date'.
• Select other objects. Chiron, a few of the largest asteroids, all objects with a mean radius above 100km, 'Far Out', 'The Goblin', ??
• Objects outbound from the solar system (5 spacecraft and Omuamua.) These their distances at a set important date. Currently thinking about doing the spacecraft along a highway, because scattering them in resemblance of their directions won't work.

The considerations for the locations are currently as follows:

• Publicly available place
• Publicly owned is prefered
• Should be accessible at any time (exception for public parks closed at night)
• No entrance fee (i.e. not inside a museum), except in 'national parks' or the like.
• Civic locations prefered
• Parks, civic plazas, libraries, etc.
• Museums are desirable
• Science and children's museums prefered
• Current tourist locations prefered
• Within the municipal bounds is prefered.
• Visibility to and from "the sun" is prefered.
• Must be located such that people may easily reach it and be able to safely take pictures
• Having a good vista when taking pictures with object is highly desirable
• Spread across the region is desired (not all along a single axis).
• Places with historic markers or status are desirable.
• Needs room to host major moons (for the planets).
• Needs room to host plaque giving info about object and the model (giving locations of the 8 majors and website info for to lookup the rest)..
• No fudging of orbit (center of object must be within the actual orbital bounds)
• Objects with higher eccentricities should be sited further out when possible.
• When objects fall outside of the municipality, canton (province, prefecture, state, etc.), or country, it is ideal to have it in a sister city, the capitol, or most visited city.
• If possible, certain notable locations should be targeted to host objects.

I have found some wonderful locations. Earth was giving me trouble until I looked very carefully and found a location that has a "wow" factor. There is a great place for Jupiter (great beyond my dreams), however since it would be inside a facility that is usually closed to the public, it fails. I am building a list of possibles for each object. I am planing of visiting many of them with a marked stick to take photos to show the size of the large objects (by inserting an image of the object to scale) and siting.

I welcome comments. Those who would like to see my current work can PM me, so I can e-mail them the .kmz and spreadsheet.

[xilman]

Originally Posted by Uncwilly

I welcome comments. Those who would like to see my current work can PM me, so I can e-mail them the .kmz and spreadsheet.

Good idea!

Presumably the model will be a projection onto a plane, or you'll be faced with some expensive earthworks and/or scaffolding. Which plane? The ecliptic is obvious but I'd argue for the invariable plane of the solar system as it's markedly more natural. Another factor for verisimilitude is to pick an epoch for the objects' positions.

Consider yourself PMed. You already have my email address I believe.

[ixfd64]

The Sagan Planet Walk in Ithaca would be a good reference: https://en.wikipedia.org/wiki/Sagan_Planet_Walk

I visited it on a trip to the East Coast several years ago.

[Uncwilly]

Originally Posted by xilman

Presumably the model will be a projection onto a plane.....
Another factor for verisimilitude is to pick an epoch for the objects' positions.

Well, I am thinking that the centre of all of the objects (sol excepted) will be between 1.25 and 2 meters above the local ground level (Jupiter will be quite large.)
With regards to locations, it is all about the distances and not the angles between the objects. If it was a snapshot of such, some would be in the water and some 'in the woods'.

Originally Posted by ixfd64

The Sagan Planet Walk in Ithaca would be a good reference: https://en.wikipedia.org/wiki/Sagan_Planet_Walk

I haven't seen that one, but I have seen the one in Washington DC. The one that I am looking at has a much larger scale, about twice the one in Maine, USA

I am aware of this page: https://en.wikipedia.org/wiki/Solar_System_model

[Spherical Cow]

Originally Posted by Uncwilly

Well, I am thinking that the centre of all of the objects (sol excepted) will be between 1.25 and 2 meters above the local ground level (Jupiter will be quite large.)

Sounds like this is going to be really impressive- I've PM'ed for the KMZ and spreadsheet. Many thanks-

Norm

[Dr Sardonicus]

Originally Posted by Uncwilly

The one that I am looking at has a much larger scale, about twice the one in Maine, USA

Hmm. The Maine model has a scale of about 1 mile per AU. So you're looking at a scale of two miles per AU, right? So, Neptune would be 60 miles or so away from Mr. Sun.

I don't know what you would do about the dwarf planets Eris (Aphelion 97.651 AU, Perihelion 37.911 AU) and Sedna (Aphelion ≈ 936 AU, Perihelion 76.0917±0.0087 AU) (figures copy/pasted from Wikipedia pages). Even Sedna's perihelion would be over 150 miles out.

[Uncwilly]

Originally Posted by Dr Sardonicus

Hmm. The Maine model has a scale of about 1 mile per AU. So you're looking at a scale of two miles per AU, right? So, Neptune would be 60 miles or so away from Mr. Sun.

I don't know what you would do about the dwarf planets Eris (Aphelion 97.651 AU, Perihelion 37.911 AU) and Sedna (Aphelion ≈ 936 AU, Perihelion 76.0917±0.0087 AU) (figures copy/pasted from Wikipedia pages). Even Sedna's perihelion would be over 150 miles out.

Scale of ~2³/₄km per AU.

Sedna would be in the capitol city of a neighboring country. I plotted locations for "The Goblin" and "Far Out" near aphelion as well. Ocean/air travel would be involved to see them.
The aphelion of Eris falls ~1km from a large, very photogenic and well known natural wonder. It works out nice. 2014 MU₆₉ has a good location. Makemake and Haumea overlap quite a bit. There are several sites that could host either or both.

It is still a work in progress. The objects over 100km really pads the list.

[Dr Sardonicus]

Originally Posted by Uncwilly

Scale of ~2³/₄km per AU.
<snip>
It is still a work in progress. The objects over 100km really pads the list.

I can't tell whether that's "two and three quarters" which is 2.75, or "two to the three-quarters power," which is about 1.68. But 1.68 kilometers is just about a mile...

Speaking of "still a work in progress" and faraway objects padding the list, I happened upon the following, pertaining to the search for "Planet Nine:" Massive Disk of Trans-Neptunian Objects Casts Doubt on Planet Nine. It says the results will be published in the Astronomical Journal.

There is an arXiv draft of the paper, SHEPHERDING IN A SELF-GRAVITATING DISK OF TRANS-NEPTUNIAN OBJECTS.

[Uncwilly]

Originally Posted by Dr Sardonicus

I can't tell whether that's "two and three quarters" which is 2.75, or "two to the three-quarters power," which is about 1.68. But 1.68 kilometers is just about a mile...

Speaking of "still a work in progress" and faraway objects padding the list, I happened upon the following, pertaining to the search for "Planet Nine:" Massive Disk of Trans-Neptunian Objects Casts Doubt on Planet Nine. It says the results will be published in the Astronomical Journal.

There is an arXiv draft of the paper, SHEPHERDING IN A SELF-GRAVITATING DISK OF TRANS-NEPTUNIAN OBJECTS.

2.75
I am aware of the P9 issue. The 'asteroids' above 100km mean radius (or diameter) [because different tables use different methods of reporting size], are all fairly close in. The closer outer objects include 1P/Halley, Chiron, 67P, etc. TNO's right now are only potential dwarf planets, 2014MU₆₉, Omuamua (at its distance at a select data in the future), Far Out, and The Goblin. I will look for some others that hit other important places to flesh it out a bit. I would like it to be the most detailed model (most objects.)