Nature does not always conform to our predispositions and preferences, to what we deem comfortable and easy to understand.

Once we overcome our fear of being tiny, we find ourselves on the threshold of a vast and awesome Universe that utterly dwarfs — in time, in space, and in potential — the tidy anthropocentric proscenium of our ancestors.

Our children long for realistic maps of the future that they can be proud of. Where are the cartographers of human purpose?

The near side of a galaxy is tens of thousands of light-years closer to us than the far side; thus we see the front as it was tens of thousands of years before the back. But typical events in galactic dynamics occupy tens of millions of years, so the error in thinking of an image of a galaxy as frozen in one moment of time is small.

When you make the finding yourself - even if you're the last person on Earth to see the light - you'll never forget it.

But I try not to think with my gut. If I'm serious about understanding the world, thinking with anything besides my brain, as tempting as that might be, is likely to get me into trouble.

For me, the most ironic token of [the first human moon landing] is the plaque signed by President Richard M. Nixon that Apollo 11 took to the moon. It reads, ‘We came in peace for all Mankind.’ As the United States was dropping seven and a half megatons of conventional explosives on small nations in Southeast Asia, we congratulated ourselves on our humanity. We would harm no one on a lifeless rock.