A Walk Through the Solar System

Scale models of the planets are popping up in cities and parks all over the country.

Markers along the Solar Walk in Gainesville, Fllorida. Artist: Elizabeth Indianos

There aren’t many ways to get a firsthand appreciation for the vastness of space. Even if someday a crew of astronauts makes the 50-million-mile journey to Mars, that won’t do much for the rest of us. But Mars—or Pluto, for that matter—are closer than you think if you’re willing to scale back, literally, your expectations.

The citizens of Cumberland, Indiana are about to join more than 20 communities around the United States that sport a scale model of the solar system in their back yards (see our interactive map). Cumberland’s model, representing the Sun and planets at a 1:1 billion scale, will span nearly three miles along the southern edge of the downtown area. Due for completion by the end of this year, the project is part of a plan to create a path for walking and biking within a larger network of trails crisscrossing the counties outside Indianapolis. The solar system model is expected to boost traffic along the trail while giving Cumberland a reputation for thinking big.

At the scale of the Cumberland model, Earth will be about 492 feet from the Sun and about half an inch in diameter. Each planet will be represented by a station or “node” with a to-scale model of the planet itself, along with images of its surface and informative text. Another node lists the spacecraft that have traveled to the outer reaches of the solar system.

Of the models already installed in the United States, most are located in downtown areas or along public paths like the one in Cumberland. The Lakeview Museum Community Solar System in Peoria, Illinois is one of the largest in the U.S., stretching for nearly 40 miles. Solar system models have sprouted up in Europe, too, from York, England to Zurich. The largest model in the world so far is in Sweden, where planets are represented by sculptures located in different cities. An even larger project is currently seeking funding in Scotland. The size of these installations shows just how big the solar system is; if they were much smaller than the Cumberland model, we wouldn’t be able to see Earth with the naked eye. Even in Sweden, Earth is only about 26 inches across.

Not all the installations begin as public works projects. Strung out along a bike path in Eugene, Oregon is another 1:1 billion-scale model like the one planned for Cumberland. Jack Van Dusen created the initial model—represented by marks painted on the bike path—as a way to show his fourth-grade son just how small and far apart the planets were. When they saw passersby stopping to study the marks, they decided to build a permanent model with steel planets fixed atop steel pyramids. A new set of informational displays is now in the works.

Parker King, the concept designer for the Cumberland model, says the Eugene solar system was his inspiration for the project. While tutoring fifth graders, King was disappointed in the resources available for teaching about the solar system. He approached the Cumberland Town Council, who were enthusiastic about the idea of creating an installation. One of King’s main goals was to make his model accurate not just in absolute, as-the-crow-flies distance between the planets, but in how long it takes to walk from one to another—many other models are built along meandering paths that increase traveling times.

Many more towns and institutions will have their own solar systems within the next few years. The National Center for Earth and Space Science Education’s model program, called Voyage, is specifically designed to be adopted by other locales around the country. The original model spans 6.5 football fields between the Air and Space Museum and the Smithsonian Castle on the National Mall in Washington, D.C. Copies of it can be purchased for $250,000, to be installed anywhere from state parks to college campuses. The copies even come with a package of supplemental resources, including training for educators and a public science program. Designed to be aesthetically pleasing, all-weather and vandal resistant, the model has already been installed in downtown Kansas City, near Houston’s Johnson Space Center and on the historic waterfront in Corpus Christi, Texas. Three more U.S. locations are in the works, according to Jeff Goldstein, Voyage’s program director, and next year the model will be offered internationally.

One of Voyage’s unique features is that its scale can even accommodate the nearest star; if Proxima Centauri were added to the D.C. model, it would be the size of a cherry and would be located on the California coast. The larger Cumberland model wouldn’t be able to fit the star on Earth.

It remains to be seen whether recently demoted Pluto will make the cut in Cumberland. Models built before Pluto got kicked out of the planetary club now face the task of addressing the rock’s new status. For now, patrons wishing to pay their respects to the former planet can hop on their bikes and ride out past Neptune. On the National Mall, signs and cards have showed up at Pluto’s node—where the poor little guy is represented by a speck far smaller than the head of a pin—reading, “Pluto, you rock!” and “Pluto will always be a planet in my heart.”

Mark Betancourt is a writer and filmmaker in New York city.

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