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.

A galaxy is composed of gas and dust and stars - billions upon billions of stars. Every star may be a sun to someone.

Those afraid of the universe as it really is, those who pretend to nonexistent knowledge and envision a Cosmos centered on human beings will prefer the fleeting comforts of superstition. They avoid rather than confront the world. But those with the courage to explore the weave and structure of the Cosmos, even where it differs profoundly from their wishes and prejudices, will penetrate its deepest mysteries.

I hold that popularization of science is successful if, at first, it does no more than spark the sense of wonder.

There are many hypotheses in physics of almost comparable brillance and elegance that have been rejected because they did not survive such a confrontation with experiment. In my view, the human condition would be greatly improved if such confrontations and willingness to reject hypotheses were a regular part of our social, political, economic, religious and cultural lives.

The politicians and the religious leaders and the weapons scientists have been at it for a long time and they've made a thorough mess of it. I mean, we're in deep trouble.

An atheist has to know a lot more than I know. An atheist is someone who knows there is no god. By some definitions atheism is very stupid.