“The total number of stars in the Universe is larger than all the grains of sand on all the beaches of the planet Earth.” – CS

I don’t think anyone can disagree; Carl Sagan was a cool dude. He was an astronomer, teacher, author, cosmologist, activist, Pulitzer Prize winner (among other awards), marijuana user and advocate, space science and exobiology pioneer. I could go on. But most of all, he was considered one of greatest popularizers of science; he made it fashionable and tangible. As the National Science Foundation declared, “…his gifts to mankind were infinite.” He taught at Cornell University for 25 years and has left his mark all over Ithaca, NY among other places.

The other day I asked Mathew what he would like to do. It was one of those perfect days, 70s, a few clouds decorating the sky with a slight breeze. He decided that he would like to do the Sagan Planet Walk. I thought it was a perfect day to walk the solar system, since we hadn’t done it recently. The Sagan Planet Walk is a walking scale model of the solar system. One of the very cool features is that the model scales the entire solar system—both planet size and distances between them—down to one five billionth of its actual size. It consists of 11 obelisks situated along a path less than a mile long through the streets of downtown Ithaca. The Planet Walk leads from the sun at the Ithaca Commons to Pluto at the Sciencenter. Yes, they still include Pluto. In 2012, the model was expanded 5,000 miles to include a representation of the sun’s closest neighboring star, Alpha Centauri, at the Imiloa Astronomy Center at the University of Hawaii, making it the largest exhibit in the world. Unfortunately, we only made it to the Sciencenter, so far.

There are several ways to do the planet walk. Last time we just walked and found each planet, no map. They do sell passports that provide you with a map, information and you can get it stamped for each planet or Sun at local stores along the way. If you purchase the passport for $4, and you get it stamped at each station, you get one free admission to the Sciencenter. Since, we are science junkies; we have a special pass that gets us into 325 science museums worldwide through the Association of Science-Technology Centers (ASTC) Travel Passport Program. Therefore, I downloaded and printed the passport from the Sciencenter’s website for free. There is also a free audio tour, which is narrated by Bill Nye the Science Guy. You simply call (703) 637-6237 or download the tour as a podcast from iTunes or at www.sciencenter.org/saganpw. We have yet to use the audio tour, perhaps next time.

Currently, the Commons is under construction and they have moved the Sun, Mercury, Venus, Earth, and Mars monuments temporarily. Not a big deal, we have seen them bunches of times and there is information about each planet/Sun on the construction wall which is still rather true to scale. It was a great day to walk the solar system. We learned a bunch of new things about our universe and we met a lot of really nice people along the way. Between Mars and Jupiter, we got to touch a real meteorite that landed in Argentina over 4,000 years ago, at the Asteroid monument.