One of Central Park’s original design features is the “Promenade”, a straight path running diagonally across the entire length of the park.  The Promenade extends approximately three-quarters of a mile, which is an optimal length for this true-scale exhibit of the Solar System, installed in 2015.

You might be wondering: at the scale of this Solar System model, how much longer would the Promenade have to be extended in order to reach the distance of the nearest star?  Well, imagine getting into an airplane, using the Promenade as a runway, and taking off to the west, flying straight ahead along an imaginary extension of the Promenade.

• After 2.6 miles, you would be near the intersection of 26th and Holly.  That would be the equivalent of the most distant man-made object: the Voyager 1 space probe.*
• At the 4-mile mark, you would fly over City Park, and at 6 miles you’d be over downtown Denver.  Keep going.
• At 18 miles you would enter the foothills, and at 26 miles you would pass over Evergreen.
• At 42 miles you would pass Mt. Evans, and at 63 miles you would pass Lake Dillon.
• At 200 miles you would fly over Grand Junction, and you would cross into Utah at 230 miles.  Keep going.
• At 515 miles you would enter Nevada, and at 689 miles you would enter California.
• At 933 miles you would reach the coast of California and start flying over the Pacific Ocean.  Keep going.
• At 1229 miles you would have traveled the distance that corresponds to one light year.
• At 3300 miles you would be able to see Hawaii out your window.  Keep going.
• At 5208 miles you would be somewhere over the middle of the vast Pacific Ocean, not far from Howland and Baker islands...

...and at that point, imagine a tennis ball floating in the ocean.  That would represent the approximate size and distance of Proxima Centauri, the nearest star to our own.**  The 5200-some miles between that tennis ball and our basketball-sized Sun in Central Park contain virtually nothing… only space.  And so far, no astronaut has traveled any farther than the Moon, which at the scale of this diagram is about three inches away from Earth.

*Currently five unmanned probes are on their way out of the Solar System.  The fastest and most distant of these, Voyager 1, was launched in 1977 and is moving away from the Sun at a speed of 17 kilometers per second.  At the scale of this diagram, Voyager 1 travels about one foot each day.
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**Proxima Centauri is a red dwarf star.  Even though it is the closest star to our Sun, it is too small and dim to be seen without a telescope.  Proxima is believed to be gravitationally-bound to the two main components of the Alpha Centauri system.  To reach them on the scale of this model, you would have to continue another 40 miles or so beyond the tennis ball that represents Proxima.  There, you would find two basketballs separated by a distance of about a half-mile, representing the stars Alpha Centauri A and B.  To observers on Earth, those two stars look like a single star, and their combined light forms the third-brightest star in our night sky.  However, Alpha Centauri is never visible from Denver; it is visible only from more southerly latitudes.