More stars than there is sand on the Earth

This winter, we took a trip to Hawaii. We ended up out on the lava rock during a solar eclipse, watching the slow progression of the earth’s shadow across the moon. We had the leisure of watching the constellations reveal themselves one star at a time. Clear skies and no city lights made for some of the best stargazing possible, with thousands of stars scattered across the night sky. What a great spot to contemplate the cosmos. The next day, we had a much better and much colder night sky experience, as we took a tour to the top of the extinct volcano of Mauna Kea. At over 4 kilometres above the ocean and two kilometres above the clouds, it is easy to see why most of the best stellar observatories are located there. As the sun sets into the ocean, the temperature drops to below freezing, and again the stars come out to dazzle the sky. Just how many stars are there up there? Only about 5,000 stars are visible to our eyes, but the observatories can see many more, and the astronomers have told us that there are about 100 billion stars in our Milky Way galaxy.

Later in the week, and back down on the warm sandy beach with lots of time on my hands, I started to wonder about an oft-quoted statement that there are more stars in the universe than there is sand on all of the beaches and all of the deserts on Earth. Of course, I had to find out if this was true; there was an awful lot of sand on Big Beach!  I took a small sample of sand, did some measuring and counting, and figured out that there were about 20,000 grains of sand in a cubic centimetre, which means that there was about 1.3 quadrillion grains of sand on the beach. Well then, there was more sand on the beach than were stars in our galaxy by a whopping amount – as much sand as roughly 13,000 galaxies worth of stars. But the quote says more stars in the universe, and there are about 10 billion galaxies visible in our universe, which means that there would to have to be another 750,000 more beaches’ worth of sand to equal this huge number of stars. The University of Hawaii looked into this matter in a much more scientific way, and they determined that there were about 7,500,000,000,000,000,000 grains of sand on Earth (that’s 7.5 quintillion, if you lost count of all those zeroes). This is far shy of the number of stars that we know of in the universe, and it looks like there are actually 133 times as many stars in all of the universe than there are grains of sand on all of the beaches and in all of the deserts on Earth. A truly humbling number of stars out there, and the best way to contemplate this is with a good drink on a beach in Hawaii.

Jeff Scott is a former councillor for the City of Kingston (Countryside District), and has contributed editorial content local publications for a number of years. He continues to live, work and write in the Countryside district of Kingston, and runs his own blog, The Countryside View. Visit his Facebook page at www.facebook.com/jeffscottthecountrysideview to read more of Jeff’s content.