“Some people think the Milky Way is a long line of stars, but it isn't. Our galaxy is a huge disk of stars millions of light-years across, and the solar system is somewhere near the outside edge of the disk.”

“While the Copernican principle comes with no guarantees that it will forever guide us to cosmic truths, it's worked quite well so far: not only is Earth not in the center of the solar system, but the solar system is not in the center of the Milky Way galaxy, the Milky Way galaxy is not in the center of the universe, and it may come to pass that our universe is just one of many that comprise a multiverse. And in case you're one of those people who thinks that the edge may be a special place, we are not at the edge of anything either.”

“If there were a map of the solar system, but instead of stars it showed people and their degrees of separation, my star would be the one you had to travel the most light-years from to get to his. You would die getting to him.”

“In this way, Edwin Hubble worked out the distances to nine different galaxies. We now know that our galaxy is only one of some hundred thousand million that can be seen using modern telescopes, each galaxy itself containing some hundred thousand million stars.”

“This whole earth which we inhabit is but a point in space. How far apart, think you, dwell the most distant inhabitants of yonder star, the breadth of whose disk cannot be appreciated by our instruments?”

“Kid says to me, "You play baseball? What position? Left out?" and gets a big laugh from the rest of the class. Kid is only one person out of 6.792 billion humans on this planet. This planet is only one-eighth of the solar system, whose sun is one of two billion stars in the Milky Way galaxy. Put it that way, the comment loses it's importance.”