thinkzone.wlonk.com

Solar System Scale Model Calculator
Instructions for Website Developers

The Main Page - SolarSystemModel.php

Use this URL to link to the Solar System Scale Model Calculator main page.

URL Query Parameters

URL query parameters may be used to pre-define the model and set options for the main page (SolarSystemModel.php), the Map page (SolarSystemMap.html), or the KML page (SolarSystem.kml.php).

These parameters are required to define the scale a model: (scale) or (obj & dia) or (obj & dist).

These parameters are required to define a location on the map: (lat & lon) or (loc).

For the Map page or KML page, the only applicable parametes are: scale, obj, dia, dist, lat, lon, loc, and the planet options.

Parameter Value Description
Scaling parameters
scale= number > 1 Model scale.
obj= sun or planet name Base object for scaling: Sun, Mercury, Venus, Earth, Mars, Ceres, Jupiter, Saturn, Uranus, Neptune, Pluto, Eris, Planet9
dia= number+m|cm|km|ft|in|mi
example: 2.5m		 Model diameter of sun or planet.
dist= number+m|cm|km|ft|in|mi
example: 1000ft		 Model distance of planet from the sun.
Location parameters
lat= -90 to 90 Latitude of center of solar system on map.
lon= -180 to 180 Longitude of center of solar system on map.
loc= lat,lon Latitude and longitude, comma-separated. (Alternative)
Section options
table= y/n (default y) Show solar system table on main page.
map= y/n (default n) Show solar system map on main page.
Units options
us= y/n (default n) Show US units (mi/ft/in) rather than metric (km/m/cm) on table.
Planet options
mercury= y/n (default y) Show Mercury.
venus= y/n (default y) Show Venus.
earth= y/n (default y) Show Earth.
mars= y/n (default y) Show Mars.
ceres= y/n (default y) Show Ceres - Asteroid Belt.
jupiter= y/n (default y) Show Jupiter.
saturn= y/n (default y) Show Saturn.
uranus= y/n (default y) Show Uranus.
neptune= y/n (default y) Show Neptune.
pluto= y/n (default y) Show Pluto - Kuiper Belt.
eris= y/n (default n) Show Eris - Scattered Disk.
planet9= y/n (default n) Show Planet 9 - Distant Detached Objects.
(Planet 9 is hypothetical. This option may be removed or renamed in future.)
Table options
rings= y/n (default n) Show rings table.
moons= y/n (default n) Show moons table.
stars= y/n (default n) Show stars and galaxies table.
minmax= y/n (default n) Show min/max distances on table.
au= y/n (default n) Show astronomical units on table.
light= y/n (default n) Show light travel times on table.

The boolean options will accept values y/n or 1/0.

Examples:

The Map Page - SolarSystemMap.html

The Map page shows nothing but a full-window Google map with the solar system KML layer applied. Use this URL to link to or embed an interactive solar system map in your webpage.

Examples:

The KML Page - SolarSystem.kml.php

This KML URL generates a KML file with the planet orbits to be applied to a map. You may reference this URL live or save this page to download a KML file.

Examples:

Note: When you download a KML file, change the file extension from ".kml.php" to ".kml".

KML Format

KML (Keyhole Markup Language) is a standard XML format for annotating maps with lines, polygons, and markers.

Many mapping tools can read KML data, including (as of 2026):

Google Maps API with GeoXML3, Google My Maps, Google Earth Pro, Google Earth Web, ArcGIS

You can read and edit KML files.

The Thinkzone Solar System Model uses KML to draw the planet orbit circles and the orbital range disks on a map.

If you look inside the KML file, you will see that each orbit circle is represented not as a circle object but as a many-sided polygon approximating a circle. The KML standard does not have any circle objects! It is not easy to calculate the points on a large circle on the surface of the earth (a slightly oblate sphere) using latitude and longitude coordinates. The Thinkzone Solar System Model Calculator does this calculation for you.

Note: An alternative to KML is GeoJSON. Thinkzone uses KML, not GeoJSON.

Methods for Showing the Map on Your Site

Here are some ways (as of 2026) to make your web page or your custom map show the planet orbits with the scale, location, and options set as you choose. If you create a custom map you may add your own content, such as markers for the locations of your physical planet markers.

Method 1. Create a map with an online maps site and import KML. Download a Solar System KML file with the scale, location, and options set as you choose. Create your own customizable map at an online maps site. Import your KML file into your map. You may add your own custom markers to your map.

Online maps sites that can import KML files include (as of 2026):

Google My Maps, Google Earth Web, ArcGIS

Method 2. Link to the Solar System Model main page. On your web page, link to the Solar System Model main page (SolarSystemModel.php), with the scale, location, and options set as you choose. Use table=y/n and map=y/n options to set whether it initially shows the table, the map, or both. The main page gives the user the freedom to explore and change the scale, location, and options.

HTML example:

<a href="https://thinkzone.wlonk.com/SS/SolarSystemModel.php?obj=Sun&dia=1m&lat=47.622493&lon=-122.352017&table=n&map=y">Solar System Scale Model Calculator</a>

Method 3. Link to the Solar System Map page. On your web page, link to the Map page (SolarSystemMap.html) with the scale, location, and options set as you choose.

HTML example:

<a href="https://thinkzone.wlonk.com/SS/SolarSystemMap.html?obj=Sun&dia=30ft&lat=47.622493&lon=-122.352017">Solar System Map</a>

Method 4. Embed the Solar System Map page. On your web page, embed (for example, with iframe) the Map page (SolarSystemMap.html) with the scale, location, and options set as you choose.

HTML example:

<iframe src="https://thinkzone.wlonk.com/SS/SolarSystemMap.html?obj=Sun&dia=30ft&lat=47.622493&lon=-122.352017" style="height:600px;width:600px"></iframe>

Methods 5. Create a map with Google Maps API and apply KML with GeoXML3. Download a Solar System KML file with the scale, location, and options set as you choose. Create your own customizable map on your web page using Google Maps API. Use a third-party tool such as GeoXML3 to apply your KML file to the Google Map. You may add your own custom markers by editing the KML or using the Maps API.

HTML/JavaScript example (2026):

<script src="https://maps.googleapis.com/maps/api/js?key=MYKEY"></script>
<script src="geoxml3.js"></script>
<script>
function initMap() {
  var map = new google.maps.Map(document.getElementById('map-canvas'), {});
  var geoXMLParser = new geoXML3.parser({map: map, zoom: true, singleInfoWindow: true});
  geoXMLParser.parse("SolarSystem.kml");
}
google.maps.event.addDomListener(window, 'load', initMap);
</script>
...
<div id="map-canvas" style="height:600px;width:600px"></div>

Draw Order / Stacking Order

Pay attention to the draw order or stacking order of objects on your custom map. Some map applications may prevent users from selecting map objects, such as the average-distance orbit circles or your custom markers, that are covered by other objects, such as the orbital range disks, even if the overlying objects are semi-transparent.

Notice that Pluto's orbital range disk overlaps Neptune's, If Pluto's orbital range disk is drawn after (over) Neptune's. then Neptune may be unselectable. Similarly, Eris's orbital range disk overlaps Pluto's.

In the Thinkzone Solar System KML file, the sun and planets are in a single folder (layer) and are ordered to ensure that all orbit circles and orbital range disks are selectable by clicking on the map. First, the orbital range disks are drawn in order by distance from the sun, except that Neptune is after (over) Pluto, and Pluto is after (over) Eris. Then, the average-distance orbit circles are drawn in order by distance from the sun.

The KML orbit circles and orbital range disks also specify their draw order or stacking order with <gx:drawOrder> tags (but these Google Earth extended tags are ignored by many mapping tools).

Map Usage Limits

This website uses Google Maps API, which has free usage limits. The free usage limits (as of 2018) are: if all users of this site generate more than about 1000 Google maps per day worldwide, this website will not generate any more maps that day for anybody. If that happens, all users will need to wait until the next day. If the maps are not working on this website, you can still download a KML file and view it using another map application. There are no limits to the number of KML files that may be generated and downloaded. You are welcome to generate all the maps you need, but please avoid generating hundreds of maps if you don't need to.

Change Log

Here is a history of changes that may affect developers who link to the Thinkzone Solar System Model or who use the Solar System KML files.

Terms of Use - KML

You may use and modify the downloaded Solar System Model KML files without restriction. The KML files are internally marked as created by thinkzone.wlonk.com, Keith Enevoldsen, with No Rights Reserved (CC0).