# Solar system model

Missing image
Jupiter.SouthStation.agr.jpg
Jupiter at South Station, part of Museum of Science, Boston scale model

Mechanical models, called orrerys, that illustrate the relative positions and motions of the planets and moons in the solar system have been built for centuries. While they often showed relative sizes, these models were usually not built to scale. The enormous ratio of interplanetary distances to planetary diameters makes constructing a scale model of the solar system a challenging task. As one example of the difficulty, the distance between the Earth and the Sun is almost 12,000 times the diameter of the Earth.

If the smaller planets are to be easily visible to the naked eye, large outdoor spaces are generally necessary, as is some means for highlighting objects that might otherwise not be noticed from a distance. The objects in such models do not move. Traditional orreries often did move and some used clockworks to make the relative speeds of objects accurate. These can be thought of as being scaled in time instead of distance.

One scale model, designed to be easily replicated, is called The Thousand-Yard Model [1] (http://www.noao.edu/education/peppercorn/pcmain.html) and spans about a kilometre. In it, the Earth is represented by a peppercorn. A school class building this model might tape the peppercorn to an index card to make it more visible. Another scale model is the 1:10 000 000 model, in which 100,000 km is represented by 1 cm. In this model, the Sun is 600m from the Kuiper belt and planet Pluto.

## Scale models in various locations

Several towns and institutions have built outdoor scale models of the solar system. Here is a table comparing these models.

 Location Scale Sun dia. Earth dia. Sun-Earth Sun-Pluto The Real Thing 1:1 1.392 Gm 12.76 Mm 149.6 Gm 5.914 Tm Upstate New York from Syracuse, New York 1:46,500,000 25.6 m 305 mm (1 ft) 3.5 km 138 km University of Maine at Presque Isle 1:93,000,000 15 m 140 mm? 1.6 km 64 km Peoria, Illinois 1:125,000,000 11 m 100 mm 1.2 km 64 km Boston Museum of Science 1:400,000,000 3.5 m 32 mm 376 m 14.9 km York 1:575,872,239 2.417 m 22.1 mm 259.73 m 10.2679 km Eugene, Oregon 1:1,000,000,000 1.39 m 12 mm 150 m 5.9 km The Sagan Planet Walk (http://www.sciencenter.org/SaganPW/) 1:5,000,000,000 278 mm 2.5 mm 30 m 1.18 km Jodrell Bank 1:5,000,000,000? 30 cm? 2.5 mm? 30 m? 1 km? The Thousand-Yard Model (http://www.noao.edu/education/peppercorn/pcmain.html) 1:6,336,000,000 20.3 cm 2 mm 25 m 983 m Saint-Louis-du-Ha! Ha!, Quebec 1:10,000,000,000 13.9 cm 1.2 mm 15 m 590 m

## A model based on a classroom globe

A classroom globe

Relating the size of the Solar system to familiar objects can make it easier for students to grasp the relative distances. Most classroom globes are 41 cm (16 inches) in diameter. If the Earth were reduced to this size, the Moon would be a 10 cm (4 inch) baseball floating 12 metres (40 feet) away. The Sun would be a beach ball 14 stories tall floating 5 kilometres (3 miles) away. Here is what a solar system built to that scale would look like. To our knowledge, the complete model has never been built.

 Body Diameter Distance from Sun Sun 44.6 m (146 ft) zero Mercury 15 cm (6") 1.9 km (1.2 mi) Venus 38 cm (15") 3.5 km (2.2 mi) Earth 41 cm (16") 4.8 km (3.0 mi) Moon 10 cm (4") 12 m (40 ft) from Earth Mars 23 cm (9") 7.2 km (4.5 mi) Jupiter 4.55 m (15 ft) 24.9 km (15.5 mi) Saturn 3.81 m (12 ft 6") 45.5 km (28.3 mi) Uranus 1.63 m (5 ft 4") 92.2 km (57.3 mi) Neptune 1.55 m (5 ft 1") 144.4 km (89.7 mi) Pluto 7 cm (3") 190 km (118 mi) α Centauri A 49.5 m (162 ft) 1,323,500 km (822,400 mi)

## See also

##### Navigation

Academic Kids Menu

• Art and Cultures
• Art (http://www.academickids.com/encyclopedia/index.php/Art)
• Architecture (http://www.academickids.com/encyclopedia/index.php/Architecture)
• Cultures (http://www.academickids.com/encyclopedia/index.php/Cultures)
• Music (http://www.academickids.com/encyclopedia/index.php/Music)
• Musical Instruments (http://academickids.com/encyclopedia/index.php/List_of_musical_instruments)
• Biographies (http://www.academickids.com/encyclopedia/index.php/Biographies)
• Clipart (http://www.academickids.com/encyclopedia/index.php/Clipart)
• Geography (http://www.academickids.com/encyclopedia/index.php/Geography)
• Countries of the World (http://www.academickids.com/encyclopedia/index.php/Countries)
• Maps (http://www.academickids.com/encyclopedia/index.php/Maps)
• Flags (http://www.academickids.com/encyclopedia/index.php/Flags)
• Continents (http://www.academickids.com/encyclopedia/index.php/Continents)
• History (http://www.academickids.com/encyclopedia/index.php/History)
• Ancient Civilizations (http://www.academickids.com/encyclopedia/index.php/Ancient_Civilizations)
• Industrial Revolution (http://www.academickids.com/encyclopedia/index.php/Industrial_Revolution)
• Middle Ages (http://www.academickids.com/encyclopedia/index.php/Middle_Ages)
• Prehistory (http://www.academickids.com/encyclopedia/index.php/Prehistory)
• Renaissance (http://www.academickids.com/encyclopedia/index.php/Renaissance)
• Timelines (http://www.academickids.com/encyclopedia/index.php/Timelines)
• United States (http://www.academickids.com/encyclopedia/index.php/United_States)
• Wars (http://www.academickids.com/encyclopedia/index.php/Wars)
• World History (http://www.academickids.com/encyclopedia/index.php/History_of_the_world)
• Human Body (http://www.academickids.com/encyclopedia/index.php/Human_Body)
• Mathematics (http://www.academickids.com/encyclopedia/index.php/Mathematics)
• Reference (http://www.academickids.com/encyclopedia/index.php/Reference)
• Science (http://www.academickids.com/encyclopedia/index.php/Science)
• Animals (http://www.academickids.com/encyclopedia/index.php/Animals)
• Aviation (http://www.academickids.com/encyclopedia/index.php/Aviation)
• Dinosaurs (http://www.academickids.com/encyclopedia/index.php/Dinosaurs)
• Earth (http://www.academickids.com/encyclopedia/index.php/Earth)
• Inventions (http://www.academickids.com/encyclopedia/index.php/Inventions)
• Physical Science (http://www.academickids.com/encyclopedia/index.php/Physical_Science)
• Plants (http://www.academickids.com/encyclopedia/index.php/Plants)
• Scientists (http://www.academickids.com/encyclopedia/index.php/Scientists)
• Social Studies (http://www.academickids.com/encyclopedia/index.php/Social_Studies)
• Anthropology (http://www.academickids.com/encyclopedia/index.php/Anthropology)
• Economics (http://www.academickids.com/encyclopedia/index.php/Economics)
• Government (http://www.academickids.com/encyclopedia/index.php/Government)
• Religion (http://www.academickids.com/encyclopedia/index.php/Religion)
• Holidays (http://www.academickids.com/encyclopedia/index.php/Holidays)
• Space and Astronomy
• Solar System (http://www.academickids.com/encyclopedia/index.php/Solar_System)
• Planets (http://www.academickids.com/encyclopedia/index.php/Planets)
• Sports (http://www.academickids.com/encyclopedia/index.php/Sports)
• Timelines (http://www.academickids.com/encyclopedia/index.php/Timelines)
• Weather (http://www.academickids.com/encyclopedia/index.php/Weather)
• US States (http://www.academickids.com/encyclopedia/index.php/US_States)

Information

• Home Page (http://academickids.com/encyclopedia/index.php)
• Contact Us (http://www.academickids.com/encyclopedia/index.php/Contactus)

• Clip Art (http://classroomclipart.com)