God and the Moon
I recently finished Carlo Revelli’s “Seven Brief Lessons on Physics” ( http://www.sevenbrieflessons.com/ ), a gift from my sister. It’s been awhile since I’ve delved very deep into physics, and it is a bit of a mind blowing read. One thing I learned is that we now believe there are trillions of galaxies, and not just the 100 billion that I had last heard. Trillions of galaxies. Galaxies average over 100 billion stars, so that’s hundreds of billions of trillions of stars. A certain percentage of those are G class stars like our Sun, and a certain percentage of those have a rocky planet the appropriate distance from the star that it could support life. So the number of rocky planets that may be able support life is amazingly high. Not “common” as far as planets go, but you know, in the billions of trillions range. On the one hand, I find this exciting - we might have friends out there! (Maybe little slimy amoeba friends, but still.) On the other hand, I now have to further adjust my i...