When studying our solar system it is very difficult to comprehend the vast distances between the planets and the small sizes of the planets when compared to our star, the Sun. PARI’s Galaxy Walk helps overcome these problems.
The Galaxy Walk starts with a brief introduction to our galaxy, the Milky Way, and then continues as a scale model of our solar system designed to provide better understanding of the positioning of planets and the immense distances separating them from the Sun and each other.
Constructed by Friends of PARI volunteers, the Galaxy Walk begins near the Cline Administration Building with a display showing the Sun 10 centimeters in diameter (about the size of a large orange). Planets and other features of the solar system are shown on displays placed appropriate distances away. The Earth, for example, is on a display about 36 feet from the Sun and is only as big as a poppy seed.
Strolling the campus and finding other displays provides a very real sense of just how vast the reaches of outer space really are. Pluto and its fellow dwarf planets in the Kuiper Belt are placed about a quarter mile from the Sun display, a nice walk up a hill on PARI’s scenic campus. There you will also find displays on the Oort cloud and Proxima Centauri (a.k.a. Alpha Centauri C), the nearest star to our sun.
To provide context, a plaque showing the distance from the orange-size Sun at PARI to our nearest star is located in an observatory building at the Kitt Peak National Observatory— near Tucson, Arizona!
The walk ends with a return to a discussion of galaxies and a look at the Great Galaxy in Andromeda, the nearest large spiral galaxy to our very own Milky Way Galaxy.