Thanks to planet walks set up around our world, you can get a sense of just how far apart the planets are from one another. One such walk, the Foster Planet Walk in Grand Rapids, Michigan, was a destination point for me recently.
|The inner planets, as depicted on the Foster Planet Walk|
Located on the beautiful campus of Aquinas College, the Foster Planet Walk begins near Albertus Hall on Robinson Road SE. Each planet is marked by an easy-to-spot boulder, including the four above that represent the inner planets. Mars is closest in the above photo, then Earth, Venus and Mercury. Now let's talk scale. The half-dozen steps between the Mars and Earth boulders above depict a distance it took the recently-landed Mars Curiosity Rover over 8 months to traverse.
I found the Foster Planet Walk to be a leisurely stroll most of the way. There is some uphill walking, but it's all paved. Take another look at the inner planets above, so close and cosy. To reach the outermost planet requires walking all the way across campus.
|Standing at Jupiter's boulder, the inner planets are visible through the far trees|
Strolling to Jupiter, the distance dramatically multiplies. The Juno spacecraft, currently headed for Jupiter, launched over a year ago. As a rough estimate using NASA's mission webpage, Juno is right now located about where the two college students are walking above. But it has to swing back around Earth next year to get a gravity-assisted boost in speed. So, let's pretend one of those college students above is the Juno spacecraft. It will take her another four years to reach the boulder with Jupiter on it.
|Looking back at the inner planets from next to the Saturn boulder|
Even standing in front of the Saturn boulder above, you can still see the inner planet boulders beyond the bridge near the top of the photo. However, this is the last point at which the planet boulders are visible from one another. Getting to Uranus and Neptune requires walking around buildings, across a parking lot and up slopes. This is where my brain started grasping, however feebly, the vast distances of our solar system.
|The long walk from Neptune to Pluto|
The above section of sidewalk is about half the distance from Neptune's marker to the Pluto boulder. A walk that started with a literal hop, skip and jump from Mercury to Venus ultimately required me to walk the full length of campus, from bottom to top. Enjoying the chilly autumn drizzle, I turned 90 degrees to the left after taking the above photo. At last I spied Pluto off by its lonesome.
|Tucked up against the backside of a campus hall, Pluto sits isolated|
Though not a planet according to current scientific classification, Pluto is a fine ambassador for the icy region on the periphery of our solar system. A walking distance of about 15 minutes for me represents a journey that is currently taking the New Horizons spacecraft nine years. From here I walked back to the inner planet boulders. The whole tour took about 45 minutes, including stops to take pictures.
For additional photos of my afternoon on the Foster Planet Walk, go here. The link at the top of this post will provide you a map and additional background information. If you are ever in Grand Rapids, Michigan, I highly recommend this attraction.
Thanks are due to space blogger Pillownaut, who made me aware of the Foster Planet Walk. Check out her Google map of Planet Walks. There is likely one near you!