When you study astronomy, everything else seems to just be about bookkeeping--minor details and decorations.

Nature is jealous of her secrets, and stingy with her clues. What really amazes me is how much we know, and how clever we have had to be to learn it. But what is really humbling is to realize how as the frontier of our knowledge expands, how the true depth and extent of our ignorance is revealed. We are just scratching the surface now.

For millennia we struggled to understand our solar system. In the 19th century we first glimpsed the world of the nearby stars, and in the twentieth century we began the exploration of the Galaxy and got our first look into the the void beyond.

I realize it sounds trite and cliched, but we are really no closer now to understanding what it all means than the ancient Babylonians and Greeks were during the Bronze Age.

The farther we sail, the further the horizon recedes before us.