Astronomers tell us that our solar system is located in a spiral arm of the Milky Way Galaxy, a flat disc-shaped cluster of stars approximately 100,000 light years across at its widest point. A light year is the distance light travels in one year. Moving at the speed of 186,000 miles per second, a beam of light traverses 5.7 trillion miles in 365 days. The size of our galaxy, then, in miles, is a staggering 5.7 trillion multiplied by 100,000. Our galaxy is estimated to contain at least 200 billion stars, half of which likely possess solar systems similar to our own. The next closest galaxy is Andromeda, a star system much like our own Milky Way, approximately 2.2 million light years away from us. Furthermore, our best telescopes can probe outward into space to a distance of over 10 billion light years and view over 50 billion galaxies, each of which possesses billions of stars. And these galaxies are the only ones we can detect with the presen...